GCSE Core Science

GCSESpecification

Science A4405

This specification is published on the AQA website (aqa.org.uk). We will let centres know in writing about anychanges to the specification. We will also publish changes on our website. The version on the website is thedefinitive version; this may differ from printed versions.

Vertical black lines indicate a significant change or addition to the previous version of this specification.

Further copies of this specification booklet are available from:

AQA Logistics Centre (Manchester), Unit 2, Wheel Forge Way, Ashburton Park,Trafford Park, Manchester, M17 1EH

Or, you can download a copy from the AQA website: aqa.org.uk

Copyright © 2011 AQA and its licensors. All rights reserved.

COPYRIGHTAQA retains the copyright on all its publications, including the specifications. However, registered centres for AQAare permitted to copy material from this specification booklet for their own internal use, with the following importantexception: AQA cannot give permission to centres to photocopy any material that is acknowledged to a third partyeven for internal use within the centre.

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The Assessment and Qualifications Alliance (AQA) is a company limited by guarantee, registered in England and Wales (company number3644723) and a registered charity (registered charity number 1073334).Registered address: AQA, Devas Street, Manchester, M15 6EX

GCSE Science A for teaching from September 2010 onwards (version 1.1)

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Contents

1 Introduction 21.1 Why choose AQA? 21.2 Why choose GCSE Science A? 31.3 How do I start using this specification? 41.4 How can I find out more? 5

2 Specification at a Glance 6

3 Subject Content 83.1 Introduction to Subject Content 83.2 How Science Works 93.3 Unit 1: Biology 1 [BL1] 123.4 Unit 2: Chemistry 1 [CH1] 313.5 Unit 3: Physics 1 [PH1] 483.6 Unit 4: Controlled Assessment [SCA4] 593.7 Unit 5: Science A 1 [SCA1] 673.8 Unit 6: Science A 2 [SCA2] 673.9 Mathematical and other requirements 68

4 Scheme of Assessment 694.1 Aims and learning outcomes 694.2 Assessment Objectives 704.3 National criteria 704.4 Previous Learning requirements 714.5 Access to assessment: diversity and inclusion 71

5 Administration 725.1 Availability of assessment units and certification 725.2 Entries 725.3 Private candidates 735.4 Access arrangements, reasonable adjustments and special consideration 735.5 Examination language 735.6 Qualification titles 735.7 Awarding grades and reporting results 745.8 Grading and tiers 765.9 Re-sits and shelf life of unit results 76

6 Controlled Assessment administration 776.1 Authentication of Controlled Assessment work 776.2 Malpractice 776.3 Teacher standardisation 786.4 Internal standardisation of marking 786.5 Annotation of Controlled Assessment work 786.6 Submitting marks and sample work for moderation 796.7 Factors affecting individual candidates 796.8 Keeping candidates’ work 796.9 Grade boundaries on Controlled Assessment 79

7 Moderation 807.1 Moderation procedures 807.2 Consortium arrangements 807.3 Procedures after moderation 80

Appendices 81A Grade descriptions 81B Spiritual, moral, ethical, social, legislative, sustainable development,

economic and cultural issues, and health and safety considerations 82C Overlaps with other qualifications 83D Wider Key Skills – Teaching, developing and providing opportunities for generating evidence 84


Introduction1.1 Why choose AQA?We, AQA, are the United Kingdom’sfavourite awarding body and morecandidates get their academicqualifications from us than fromany other body. But whyare we so popular?

We understand the different requirements of eachsubject by working with teachers. Our GCSEs:

■ help candidates to achieve their full potential

■ are relevant for today’s challenges

■ are manageable for schools and colleges

■ are easy for candidates of all levels of ability tounderstand

■ lead to accurate results, delivered on time

■ are affordable and value for money.

We provide a wide range of support services forteachers, including:

■ access to subject departments

■ training for teachers, including practical teachingstrategies and methods that work, presented bysenior examiners

■ individual support for Controlled Assessment

■ 24-hour support through our website and onlinewith Ask AQA

■ past question papers and mark schemes

■ a wide range of printed and electronic resourcesfor teachers and candidates

■ free online results analysis, with Enhanced ResultsAnalysis.

We are an educational charity focused on the needs of the learner. All our income is spent on improvingthe quality of our specifications, examinations and support services. We don’t aim to profit fromeducation, we want you to.

If you are already a customer we thank you for your support. If you are thinking of joining us we look forward towelcoming you.

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1.2 Why choose GCSE Science A?

GCSE Science A enables you to provide a Key Stage 4science course for learners of any ability, whether theyintend to study science further or not. The specificationpresents biology, chemistry and physics in separateteaching and learning units, with a choice of two routesfor assessment and Controlled Assessment Unit. Thiscourse provides a firm foundation for progression toAS and A-level Science.

The model of Controlled Assessment, InvestigativeSkills Assignment (ISA), is straightforward and theprevious version proved popular with teachers.

Two routes through GCSE Science A are available:

■ Route 1 offers separate assessments of biology,chemistry and physics, together with theControlled Assessment

■ Route 2 offers assessments combining biology,chemistry and physics, together with theControlled Assessment. The subjects are notintegrated and can still be separately taught.

The different routes are offered to suit differentmethods of curriculum planning. For example, Route 1could suit centres teaching KS4 over three years toprepare learners for separate GCSEs in biology,chemistry and physics, while Route 2 could enablecentres to teach biology, chemistry and physicsconcurrently throughout KS4 to learners preparing fortwo science GCSEs.

During the development of our specifications, we havebeen careful to ensure natural progression from KS3and we have paid attention to the Assessing of Pupils’Progress approach developed by National Strategies.In Unit 4, we have signposted the assessment focusthreads to match those used in KS3.

When our science AS and A-levels were developed forfirst teaching from September 2008, we were verycareful to ensure that there was no ‘gap’ so thatlearners could easily progress from KS4. We used thesame model of internal assessment (ISAs). Researchinto the outcomes of learners at GCSE and A-level hasshown that we were successful in ensuring a smoothtransition. A-levels are due to be redeveloped to followfrom this GCSE development, and we will continue toensure our portfolio of specifications offers goodprogression routes.

When developing this specification, we’ve retainedwhat you’ve told us you like, and changed what you’vetold us we could improve.

We’ve kept:

■ a lot of the biology, chemistry and physics contentin our current specifications, so you can still use thebooks and most of the resources you’ve got now

■ guidance in each sub-section showing how thebiology, chemistry and physics can be used toteach the wider implications of how science works

■ separate assessments for biology, chemistry andphysics so you can teach the sciences separately ifyou want

■ a unitised approach to assessment, which enablesstaged assessment but does not require it – allassessments could be taken at the end of thecourse

■ ISAs – Our ISA tests are one of the most popularfeatures of our current specifications, and the newControlled Assessment ISA has been updated tomeet the requirements of the current regulations.

We’ve added:

■ an alternative assessment route, with combinedassessments that could facilitate someapproaches to curriculum planning

■ examples of practical work that could supportteaching in each sub-section. Full details areincluded in our resources.

We’ve changed:

■ some of the content following the feedback we’vereceived; this has enabled us to update andrefresh the subject content

■ the style of the exams. There are no objectivetests with separate answer sheets that candidateshave to complete. The three exams all have openquestions as well as closed questions.

GCSE Science A is one of many qualifications thatAQA offers for Key Stage 4. AQA’s range, whichincludes GCSEs, Diplomas and Entry Levelqualifications, enables teachers to select and designappropriate courses for all learners. Science A is one offive related GCSE specifications that allow biology,chemistry and physics to be taught separately with apure science approach. We also offer two GCSEspecifications that are integrated and which put thescientific content into everyday contexts. Our GCSEsuite is:

■ Science A

■ Science B

■ Biology

■ Chemistry

■ Physics

■ Additional Science

■ Additional Applied Science.

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Each qualification is a single GCSE award, andprogression routes are flexible. Science A could befollowed by Additional Science, or equally by AdditionalApplied Science. Similarly, Science B could lead toeither Additional Science or Additional AppliedScience. Our separate science GCSEs have commonunits with Science A and Additional Science, enablingco-teaching following single, double or triple scienceroutes. This also facilitates a compressed KS3,followed by the teaching of separate science GCSEsover three years.

Both GCSE Science A and GCSE Science B cover theProgramme of Study for KS4, enabling centres to meetthe entitlement requirements of the National Curriculumat KS4. In GCSE Science A, biology, chemistry andphysics can be taught separately by subjectspecialists, since the content is not integrated but ispresented in discrete units. GCSE Science B is anintegrated science specification with a context-ledapproach.

With the exception of GCSE Science B, which is a newdevelopment, AQA’s science GCSEs have evolvedfrom our current specifications. Some changes havebeen required by regulations. In our work, we’ve takenadvice from a wide range of teachers andorganisations with an interest in science education.

In addition to this specification and the associatedspecimen papers, we offer a wide range of relatedsupport and resources for teachers, much of it free.This includes:

■ Preparing to Teach meetings

■ online schemes of work

■ ideas for practical work including worksheets andtechnician guidance

■ practice tests for homework

■ our Enhanced Results Analysis service.

This support is accessible through a web-based portalcalled The Science Lab.

1.3 How do I start using this specification?

Step Two

Inform your Examinations Officer of your choice toensure you receive all your examination material. YourExaminations Officer will make sure that your centre isregistered with AQA and will complete the Intention toEnter and Estimated Entries when required to do so.

If your centre has not used AQA for any examinationsin the past, please contact our centre approval team [email protected]

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To ensure you receive all the teaching and examinationmaterial, it is important that the person responsible formaking the decision to teach AQA informs both AQAand their Examinations Officer.

Step One

To confirm you will be teaching this specification pleasesign up to teach and complete the online form. You willthen receive your free GCSE Sciences welcomepack(s) that contains teaching and support material.

Teacher Support meetings

Details of the full range of our Teacher Supportmeetings are available on our website ataqa.org.uk/support-teachers

There is also a link to our fast and convenientonline booking system for Teacher Supportmeetings at events.aqa.org.uk

Latest information online

You can find out more including the latest news,how to register to use Enhanced Results Analysis,support and downloadable resources on ourwebsite at aqa.org.uk

Ask AQA

You have 24-hour access to useful information andanswers to the most commonly asked questionsat aqa.org.uk/askaqa

If the answer to your question is not available, youcan submit a query through Ask AQA and we willrespond within two working days.

Speak to your subject team

You can talk directly to the GCSE Sciences subjectteam about this specification on 08442 090415 ore-mail [email protected]


1.4 How can I find out more?

You can choose to find out more about this specification or the services that AQA offers in a number of ways.

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Specification at a Glance

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Two routes are available, to suit different methods of curriculum planning in centres:

■ Route 1 Units 1, 2, 3 and 4

■ Route 2 Units 5, 6 and 4

For Route 1, separate exams in biology, chemistry and physics are taken, together with the ControlledAssessment. For Route 2, combined exams in biology, chemistry and physics are taken, together with theControlled Assessment.


Unit 1: Biology 1

Written paper – 1 hour

60 marks – 25%

Structured and closed questions

At least one question assessing Quality of WrittenCommunication in a science context

Unit 4: Controlled Assessment

Investigative Skills Assignment – two written assessments plusone or two lessons for practical work and data processing

50 marks – 25%

Controlled Assessment:

■ we set the ISAs and send you all the information before thecourse starts

■ you choose which of several ISAs to do and when

■ your candidates do the ISA test in class time

■ you mark their tests using marking guidance from us

■ we moderate your marks.

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Unit 2: Chemistry 1


60 marks – 25%



Unit 3: Physics 1


60 marks – 25%



Unit 5: Science A1

Written paper – 1 hour 30 minutes

90 marks – 35%



Assesses:

Biology 1 (B1.1 to B1.3)

Chemistry 1 (C1.1 to C1.4)

Physics 1 (P1.1 to P1.3)

Unit 6: Science A2

Written paper – 1 hour 30 minutes

90 marks – 40%



Assesses:

Biology 1 (B1.4 to B1.8)

Chemistry 1 (C1.5 to C1.7)

Physics 1 (P1.4 to P1.5)

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GCSE SCIENCE AOR

4406EITHER

4405


Subject Content3.1 Introduction to Subject Content

The subject content of this specification is presented infive sections:

■ How Science Works

■ the three sections of substantive content, Biology1, Chemistry 1, Physics 1

■ and the Controlled Assessment (Unit 4).

It is intended that the How Science Works content isintegrated and delivered not only through theControlled Assessment but also through the context ofthe content of Biology 1, Chemistry 1 and Physics 1.

The organisation of each sub-section of thesubstantive content is designed to facilitate thisapproach. Each of the sub-sections of Biology 1,Chemistry 1 and Physics 1 starts with the statement:

‘Candidates should use their skills, knowledge andunderstanding to: ’.

This introduces a number of activities, for example:

■ evaluating different methods of generatingelectricity

These activities are intended to enable candidates todevelop the skills, knowledge and understanding ofHow Science Works.

Other aspects of the skills, knowledge andunderstanding of How Science Works will be betterdeveloped through investigative work and it isexpected that teachers will adopt a ‘practical enquiry’approach to the teaching of many topics.

The subject content is presented in two columns. Theleft-hand column lists the content that needs to be

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delivered. The right-hand column contains guidance andexpansion of the content to aid teachers in delivering itand gives further details of what will be examined.

At the end of each section there is a list of ideas forinvestigative practical work that could be used to helpcandidates develop their practical enquiry skills tounderstand and engage with the content.

Opportunities to carry out practical work should beprovided in the context of each section. Theseopportunities should allow candidates to:

■ use their knowledge and understanding to posescientific questions and define scientific problems

■ plan and carry out investigative activities, includingappropriate risk management, in a range ofcontexts

■ collect, select, process, analyse and interpret bothprimary and secondary data to provide evidence

■ evaluate their methodology, evidence and data.

In the written papers, questions will be set thatexamine How Science Works in biology, chemistry andphysics contexts.

Examination questions will use examples that are bothfamiliar and unfamiliar to candidates. All applicationswill use the knowledge and understanding developedthrough the substantive content.

Tiering of subject content

In this specification there is additional content forHigher Tier candidates. This is denoted in the subjectcontent in bold type and annotated as HT only inSections 3.3 to 3.5.


3.2 How Science Works

This section is the content underpinning the sciencethat candidates need to know and understand.Candidates will be tested on How Science Works inboth written papers and the Controlled Assessment.

The scientific terms used in this section are clearlydefined by the ASE in The Language of Measurement:Terminology used in school science investigations(Association for Science Education, 2010). Teachersshould ensure that they, and their candidates, arefamiliar with these terms. Definitions of the terms willnot be required in assessments, but candidates will beexpected to use them correctly.

The thinking behind the doing

Science attempts to explain the world in which we live.It provides technologies that have had a great impacton our society and the environment. Scientists try toexplain phenomena and solve problems usingevidence. The data to be used as evidence must berepeatable, reproducible and valid, as only then canappropriate conclusions be made.

A scientifically literate person should, amongst otherthings, be equipped to question, and engage in debateon, the evidence used in decision-making.

The repeatability and the reproducibility of evidencerefers to how much we trust the data. The validity ofevidence depends on these, as well as on whether theresearch answers the question. If the data is notrepeatable or reproducible the research cannot be valid.

To ensure the repeatability, reproducibility and validity ofevidence, scientists consider a range of ideas thatrelate to:

■ how we observe the world

■ designing investigations so that patterns andrelationships between variables may be identified

■ making measurements by selecting and usinginstruments effectively

■ presenting and representing data

■ identifying patterns and relationships and makingsuitable conclusions.

These ideas inform decisions and are central toscience education. They constitute the ‘thinking behindthe doing’ that is a necessary complement to thesubject content of biology, chemistry and physics.

Fundamental ideas

Evidence must be approached with a critical eye. It isnecessary to look closely at how measurements havebeen made and what links have been established.Scientific evidence provides a powerful means offorming opinions. These ideas pervade all of HowScience Works.

■ It is necessary to distinguish between opinionbased on valid, repeatable and reproducibleevidence and opinion based on non-scientificideas (prejudices, whim or hearsay).

■ Scientific investigations often seek to identify linksbetween two or more variables. These links may be:

– causal, in that a change in one variable causesa change in another

– due to association, in that changes in onevariable and a second variable are linked by athird variable

– due to chance occurrence.

■ Evidence must be looked at carefully to make surethat it is:

– repeatable

– reproducible

– valid.

Observation as a stimulus to investigation

Observation is the link between the real world andscientific ideas. When we observe objects, organismsor events we do so using existing knowledge.Observations may suggest hypotheses that canbe tested.

■ A hypothesis is a proposal intended to explaincertain facts or observations.

■ A prediction is a statement about the waysomething will happen in the future.

■ Observations can lead to the start of aninvestigation, experiment or survey. Existingmodels can be used creatively to suggestexplanations for observations (hypotheses).Careful observation is necessary before decidingwhich variables are the most important.Hypotheses can then be used to makepredictions that can be tested.

■ Data from testing a prediction can support orrefute the hypothesis or lead to a new hypothesis.

■ If the hypotheses and models we have available tous do not completely match our data orobservations, we need to check the validity of ourobservations or data, or amend the models.

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Designing an investigationAn investigation is an attempt to determine whether ornot there is a relationship between variables. It istherefore necessary to identify and understand thevariables in an investigation. The design of aninvestigation should be scrutinised when evaluating thevalidity of the evidence it has produced.

■ An independent variable is one that is changed orselected by the investigator. The dependentvariable is measured for each change in theindependent variable.

■ For a measurement to be valid it must measureonly the appropriate variable.

■ A fair test is one in which only the independentvariable affects the dependent variable, as allother variables are kept the same. These arecalled control variables.

■ When using large-scale survey results, it isnecessary to select data from conditions that aresimilar.

■ Control groups are often used in biological andmedical research to ensure that observed effectsare due to changes in the independent variablealone.

■ Care is needed in selecting values of variables tobe recorded in an investigation. A trial run will helpidentify appropriate values to be recorded, suchas the number of repeated readings needed andtheir range and interval.

■ An accurate measurement is one that is close tothe true value.

■ The design of an investigation must provide datawith sufficient precision to form a valid conclusion.

Making measurements

When making measurements we must consider suchissues as inherent variation due to variables that havenot been controlled, human error and thecharacteristics of the instruments used. Evidenceshould be evaluated with the repeatability and validityof the measurements that have been made in mind.

■ There will always be some variation in the actualvalue of a variable, no matter how hard we try torepeat an event.

■ The resolution of an instrument refers to thesmallest change in a value that can be detected.

■ Even when an instrument is used correctly, humanerror may occur; this could produce randomdifferences in repeated readings or a systematicshift from the true value.

■ Random error can result from inconsistentapplication of a technique. Systematic error canresult from consistent misapplication of atechnique.

■ Any anomalous values should be examined to tryto identify the cause and, if a product of a poormeasurement, ignored.

Presenting data

To explain the relationship between two or morevariables, data may be presented in such a way as tomake the patterns more evident. There is a linkbetween the type of graph used and the type ofvariable represented. The choice of graphicalrepresentation depends upon the type of variablerepresented.

■ The range of the data refers to the maximum andminimum values.

■ The mean (or average) of the data refers to thesum of all the measurements divided by thenumber of measurements taken.

■ Tables are an effective means of displaying databut are limited in how they portray the design ofan investigation.

■ Bar charts can be used to display data in whichone of the variables is categoric.

■ Line graphs can be used to display data in whichboth the independent and dependent variablesare continuous.

■ Scattergrams can be used to show an associationbetween two variables.

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Using data to draw conclusionsThe patterns and relationships observed in datarepresent the behaviour of the variables in aninvestigation. However, it is necessary to look atpatterns and relationships between variables with thelimitations of the data in mind in order to drawconclusions.

■ Patterns in tables and graphs can be used toidentify anomalous data that require furtherconsideration.

■ A line of best fit can be used to illustrate theunderlying relationship between variables.

■ Conclusions must be limited by, and not gobeyond, the data available.

Evaluation

In evaluating a whole investigation the repeatability,reproducibility and validity of the data obtained must beconsidered.

Societal aspects of scientific evidence

A judgement or decision relating to social-scientificissues may not be based on evidence alone, as othersocietal factors may be relevant.

■ Evidence must be scrutinised for any potentialbias of the experimenter, such as funding sourcesor allegiances.

■ Evidence can be accorded undue weight, ordismissed too lightly, simply because of its politicalsignificance. If the consequences of the evidencecould provoke public or political disquiet, theevidence may be downplayed.

■ The status of the experimenter may influence theweight placed on evidence; for instance,academic or professional status, experience andauthority.

■ Scientific knowledge gained through investigationscan be the basis for technological developments.

■ Developments in science and technology haveethical, social, economic or environmentalconsequences, which should always be taken intoaccount when evaluating the impacts of any newdevelopments.

■ Advancements in science can have ethicalimplications. The effects of these must be takeninto account in a balanced way to facilitatedecision making.

■ Decisions are made by individuals and by societyon issues relating to science and technology.

Limitations of scientific evidence

Science can help us in many ways but it cannot supplyall the answers.

■ We are still finding out about things anddeveloping our scientific knowledge.

■ There are some questions that we cannot answer,maybe because we do not have enoughrepeatable, reproducible and valid evidence.

■ There are some questions that science cannotanswer directly. These tend to be questions wherebeliefs, opinions and ethics are important.

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GCSE Science A for teaching from September 2011 onwards (version 1.1)S

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Additional guidance:

Candidates will be given data to work from.


Knowledge and understanding of the specific functionsof nutrients and the effects of any deficiency in the dietare not required.


The effect of exercise on breathing and heart rate is notrequired.

3.3 Unit 1: Biology 1

B1.1 Keeping healthy

A combination of a balanced diet and regular exercise is needed to help keep the body healthy. Our bodiesprovide an excellent environment for many microbes which can make us ill once they are inside us. Our bodiesneed to stop most microbes getting in and deal with any microbes which do get in. Vaccination can be used toprevent infection.

Candidates should use their skills, knowledgeand understanding to:■ evaluate information about the effect of food

on health

■ evaluate information about the effect of lifestyleon development of disease

■ analyse and evaluate claims made by slimmingprogrammes, and slimming products.

B1.1.1 Diet and exercise

a) A healthy diet contains the right balance of thedifferent foods you need and the right amount ofenergy. Carbohydrates, fats and proteins are usedby the body to release energy and to build cells.Mineral ions and vitamins are needed in smallamounts for healthy functioning of the body.A person is malnourished if their diet is notbalanced. This may lead to a person beingoverweight or underweight. An unbalanceddiet may also lead to deficiency diseases orconditions such as Type 2 diabetes.

b) A person loses mass when the energy contentof the food taken in is less than the amount ofenergy expended by the body. Exercise increasesthe amount of energy expended by the body.

c) The rate at which all the chemical reactions in thecells of the body are carried out (the metabolic rate)varies with the amount of activity you do and theproportion of muscle to fat in your body. Metabolicrate may be affected by inherited factors.

d) Inherited factors also affect our health; for examplecholesterol level.

e) People who exercise regularly are usuallyhealthier than people who take little exercise.

B1.1.2 How our bodies defend themselves against infectious diseases

Candidates should use their skills, knowledgeand understanding to:■ relate the contribution of Semmelweis in

controlling infection to solving modern problemswith the spread of infection in hospitals

■ explain how the treatment of disease has changedas a result of increased understanding of the actionof antibiotics and immunity

■ evaluate the consequences of mutations of bacteriaand viruses in relation to epidemics and pandemics

■ evaluate the advantages and disadvantages ofbeing vaccinated against a particular disease.

a) Microorganisms that cause infectious diseaseare called pathogens.

b) Bacteria and viruses may reproduce rapidly insidethe body and may produce poisons (toxins) thatmake us feel ill. Viruses damage the cells in whichthey reproduce.

c) The body has different ways of protecting itselfagainst pathogens.

d) White blood cells help to defend against pathogens by:

■ ingesting pathogens

■ producing antibodies, which destroy particularbacteria or viruses

■ producing antitoxins, which counteract the toxinsreleased by the pathogens.

e) The immune system of the body produces specificantibodies to kill a particular pathogen. This leads toimmunity from that pathogen. In some cases, deador inactivated pathogens stimulate antibody production.If a large proportion of the population is immune toa pathogen, the spread of the pathogen is verymuch reduced.

f) Semmelweis recognised the importance ofhand-washing in the prevention of spreading someinfectious diseases. By insisting that doctors washedtheir hands before examining patients, he greatlyreduced the number of deaths from infectiousdiseases in his hospital.


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Knowledge of the structure of bacteria and viruses isnot required.


Candidates should be aware that it is difficult to developdrugs that kill viruses without also damaging the body’stissues.

Knowledge of the development of resistance in bacteriais limited to the fact that pathogens mutate, producingresistant strains.

HT only


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Details of vaccination schedules and side effectsassociated with specific vaccines are not required.

g) Some medicines, including painkillers, help to relievethe symptoms of infectious disease, but do not killthe pathogens.

h) Antibiotics, including penicillin, are medicines thathelp to cure bacterial disease by killing infectiousbacteria inside the body. Antibiotics cannot be usedto kill viral pathogens, which live and reproduceinside cells. It is important that specific bacteriashould be treated by specific antibiotics. The useof antibiotics has greatly reduced deaths frominfectious bacterial diseases. Overuse andinappropriate use of antibiotics has increasedthe rate of antibiotic resistant strains of bacteria.

i) Many strains of bacteria, including MRSA, havedeveloped resistance to antibiotics as a result ofnatural selection. To prevent further resistancearising it is important to avoid overuse of antibiotics.

j) Mutations of pathogens produce new strains.Antibiotics and vaccinations may no longer beeffective against a new resistant strain of thepathogen. The new strain will then spread rapidlybecause people are not immune to it and there isno effective treatment.

Higher Tier candidates should understand that:

■ antibiotics kill individual pathogens of thenon-resistant strain

■ individual resistant pathogens survive andreproduce, so the population of the resistantstrain increases

■ now, antibiotics are no longer used to treatnon-serious infections, such as mild throatinfections, so that the rate of development ofresistant strains is slowed down.

k) The development of antibiotic-resistant strains of bacterianecessitates the development of new antibiotics.

l) People can be immunised against a disease byintroducing small quantities of dead or inactive formsof the pathogen into the body (vaccination). Vaccinesstimulate the white blood cells to produce antibodiesthat destroy the pathogens. This makes the personimmune to future infections by the microorganism.The body can respond by rapidly making the correctantibody, in the same way as if the person hadpreviously had the disease.

MMR vaccine is used to protect children againstmeasles, mumps and rubella.

m) Uncontaminated cultures of microorganisms arerequired for investigating the action of disinfectantsand antibiotics.

For this:

■ Petri dishes and culture media must be sterilisedbefore use to kill unwanted microorganisms

■ inoculating loops used to transfer microorganismsto the media must be sterilised by passing themthrough a flame

■ the lid of the Petri dish should be secured withadhesive tape to prevent microorganisms fromthe air contaminating the culture.

n) In school and college laboratories, cultures shouldbe incubated at a maximum temperature of 25°C,which greatly reduces the likelihood of growth ofpathogens that might be harmful to humans.

o) In industrial conditions higher temperatures canproduce more rapid growth.

Suggested ideas for practical work to develop skills and understanding include the following:

■ investigate the effectiveness of various antibiotic discs in killing bacteria

■ growing microorganisms in Petri dishes to demonstrate sterile technique and growing pure cultures

■ the use of pre-inoculated agar in Petri dishes to evaluate the effect of disinfectants and antibiotics

■ computer simulations to model the effect of: balanced and unbalanced diets and exercise; the growth ofbacterial colonies in varying conditions; action of the immune system and the effect of antibiotics andvaccines.

B1.2 Nerves and hormones

The nervous system and hormones enable us to respond to external changes. They also help us to controlconditions inside our bodies. Hormones are used in some forms of contraception and in fertility treatments. Plantsalso produce hormones and respond to external stimuli.

Candidates should use their skills, knowledgeand understanding to:■ evaluate the benefits of, and the problems that may

arise from, the use of hormones to control fertility,including In Vitro Fertilisation (IVF)

■ evaluate the use of plant hormones in horticulture asweedkillers and to encourage the rooting ofplant cuttings.


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B1.2.1 The nervous system

a) The nervous system enables humans to react to theirsurroundings and coordinate their behaviour.

b) Cells called receptors detect stimuli (changes in theenvironment).

Receptors and the stimuli they detect include:

■ receptors in the eyes that are sensitive to light

■ receptors in the ears that are sensitive to sound

■ receptors in the ears that are sensitive to changesin position and enable us to keep our balance

■ receptors on the tongue and in the nose that aresensitive to chemicals and enable us to tasteand to smell

■ receptors in the skin that are sensitive to touch,pressure, pain and temperature changes.

c) Light receptor cells, like most animal cells, have anucleus, cytoplasm and cell membrane.

d) Information from receptors passes along cells(neurones) in nerves to the brain. The braincoordinates the response. Reflex actions areautomatic and rapid. They often involve sensory,relay and motor neurones.


Knowledge and understanding of the structure andfunctions of sense organs such as the eye and the earare not required.


A knowledge of the functions of the cell components isnot required.

e) Candidates should understand the role of receptors,sensory neurones, motor neurones, relay neurones,synapses and effectors in simple reflex actions.

In a simple reflex action:

■ impulses from a receptor pass along a sensoryneurone to the central nervous system

■ at a junction (synapse) between a sensory neuroneand a relay neurone in the central nervous system,a chemical is released that causes an impulse to besent along a relay neurone

■ a chemical is then released at the synapsebetween a relay neurone and motor neurone inthe central nervous system, causing impulses tobe sent along a motor neurone to the organ(the effector) that brings about the response

■ the effector is either a muscle or a gland, a muscleresponds by contracting and a gland respondsby releasing (secreting) chemical substances.

B1.2.2 Control in the human body

a) Internal conditions that are controlled include:

■ the water content of the body – water leavesthe body via the lungs when we breathe out andvia the skin when we sweat to cool us down, andexcess water is lost via the kidneys in the urine

■ the ion content of the body – ions are lost via theskin when we sweat and excess ions are lost viathe kidneys in the urine

■ temperature – to maintain the temperature atwhich enzymes work best

■ blood sugar levels – to provide the cells witha constant supply of energy.

b) Many processes within the body are coordinatedby chemical substances called hormones. Hormonesare secreted by glands and are usually transportedto their target organs by the bloodstream.


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Details of the action of the skin and kidneys and thecontrol of blood sugar are not required.


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c) Hormones regulate the functions of many organsand cells. For example, the monthly release of anegg from a woman’s ovaries and the changes in thethickness of the lining of her womb are controlled byhormones secreted by the pituitary gland and bythe ovaries.

d) Several hormones are involved in the menstrual cycleof a woman. Hormones are involved in promotingthe release of an egg:

■ follicle stimulating hormone (FSH) is secreted bythe pituitary gland and causes eggs to mature inthe ovaries. It also stimulates the ovaries toproduce hormones including oestrogen

■ luteinising hormone (LH) stimulates the releaseof eggs from the ovary

■ oestrogen is secreted by the ovaries andinhibits the further production of FSH.

e) The uses of hormones in controlling fertility include:

■ giving oral contraceptives that contain hormonesto inhibit FSH production so that no eggs mature

– oral contraceptives may contain oestrogen andprogesterone to inhibit egg maturation

– the first birth-control pills contained largeamounts of oestrogen. These resulted inwomen suffering significant side effects

– birth-control pills now contain a much lowerdose of oestrogen, or are progesterone only

– progesterone-only pills lead to fewer sideeffects

■ giving FSH and LH in a ‘fertility drug’ to a womanwhose own level of FSH is too low to stimulateeggs to mature, for example in In Vitro Fertilisation(IVF) treatment

– IVF involves giving a mother FSH and LH tostimulate the maturation of several eggs.The eggs are collected from the mother andfertilised by sperm from the father. The fertilisedeggs develop into embryos. At the stage whenthey are tiny balls of cells, one or two embryosare inserted into the mother’s uterus (womb).


Knowledge of the role of progesterone in the naturalmenstrual cycle, including details of negative feedback,is not required.

B1.2.3 Control in plants

a) Plants are sensitive to light, moisture and gravity:

■ their shoots grow towards light and against theforce of gravity

■ their roots grow towards moisture and in thedirection of the force of gravity.

b) Plants produce hormones to coordinate andcontrol growth. Auxin controls phototropismand gravitropism (geotropism).

c) The responses of plant roots and shoots to light,gravity and moisture are the result of unequaldistribution of hormones, causing unequalgrowth rates.

d) Plant growth hormones are used in agricultureand horticulture as weed killers and as rootinghormones.


■ investigation into candidates’ reaction times – measuring reaction times using metre rules, stop clocks or ICT

■ using forehead thermometers before and after exercise

■ demonstrating the speed of transmission along nerves by candidates standing in a semi-circle and holdinghands and squeezing with eyes closed

■ design an investigation to measure the sensitivity of the skin

■ demonstrating the knee jerk reaction

■ investigation to measure the amount of sweat produced during exercise

■ investigate:

– the effect of light on the growth of seedlings

– the effect of gravity on growth in germinating seedlings

– the effect of water on the growth of seedlings

– using a motion sensor to measure the growth of plants and seedlings

– the effect of rooting compounds and weed killers on the growth of plants.


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Candidates should understand the role of auxin inphototropism and gravitropism.


Names of specific weed killers and rooting hormonesare not required.



Classification of drug types is not required.


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Candidates should understand that tissues and animalsare used as models to predict how the drugs maybehave in humans.

B1.3 The use and abuse of drugs

Drugs affect our body chemistry. Medical drugs are developed and tested before being used to relieve illness ordisease. Drugs may also be used recreationally as people like the effect on the body. Some drugs are addictive.Some athletes take drugs to improve performance. People cannot make sensible decisions about drugs unlessthey know their full effects.

Candidates should use their skills, knowledgeand understanding to:■ evaluate the effect of statins in cardiovascular

disease

■ evaluate different types of drugs and why somepeople use illegal drugs for recreation

■ evaluate claims made about the effect of prescribedand non-prescribed drugs on health

■ consider the possible progression from recreationaldrugs to hard drugs

■ evaluate the use of drugs to enhance performancein sport and to consider the ethical implications oftheir use.

B1.3.1 Drugs

a) Scientists are continually developing new drugs.

b) When new medical drugs are devised, they haveto be extensively tested and trialled before beingused. Drugs are tested in a series of stages to findout if they are safe and effective.

New drugs are extensively tested for toxicity,efficacy and dose:

■ in the laboratory, using cells, tissues andlive animals

■ in clinical trials involving healthy volunteersand patients. Very low doses of the drug aregiven at the start of the clinical trial. If the drug isfound to be safe, further clinical trials are carriedout to find the optimum dose for the drug. In somedouble blind trials, some patients are given aplacebo, which does not contain the drug. Neitherthe doctors nor the patients know who hasreceived a placebo and who has received thedrug until the trial is complete.

c) Candidates should be aware of the use of statins inlowering the risk of heart and circulatory diseases.

d) Thalidomide is a drug that was developed as asleeping pill. It was also found to be effective inrelieving morning sickness in pregnant women.

Thalidomide had not been tested for use in pregnantwomen. Unfortunately, many babies born to motherswho took the drug were born with severe limbabnormalities. The drug was then banned. As aresult, drug testing has become much more rigorous.More recently, thalidomide has been usedsuccessfully in the treatment of leprosy and otherdiseases.

e) Candidates should be aware of the effects of misuseof the legal recreational drugs, alcohol and nicotine. Candidates should understand that the misuse of theillegal recreational drugs ecstasy, cannabis andheroin may have adverse effects on the heart andcirculatory system.

f) Cannabis is an illegal drug. Cannabis smoke containschemicals which may cause mental illness insome people.

g) The overall impact of legal drugs (prescribed andnon-prescribed) on health is much greater than theimpact of illegal drugs because far more peopleuse them.

h) Drugs change the chemical processes in peoples’bodies so that they may become dependent oraddicted to the drug and suffer withdrawalsymptoms without them. Heroin and cocaine arevery addictive.

i) There are several types of drug that an athlete canuse to enhance performance. Some of these drugsare banned by law and some are legally availableon prescription, but all are prohibited by sportingregulations. Examples include stimulants that boostbodily functions such as heart rate; and anabolicsteroids which stimulate muscle growth.


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Knowledge and understanding of the specific effects ofrecreational drugs on the body, except for cannabis arenot required. The legal classification of specific drugs isnot required.


Awareness of the benefits of medical drugs, the impactof non-medical drugs such as alcohol and the possiblemisuse of legal drugs should be considered.


Knowledge of the mode of action of steroids and otherperformance-enhancing drugs is not required.

B1.4 Interdependence and adaptation

Organisms are well adapted to survive in their normal environment. Population size depends on a variety of factorsincluding competition, predation, disease and human influences. Changes in the environment may affect thedistribution and behaviour of organisms.

Candidates should use their skills, knowledgeand understanding to:■ suggest how organisms are adapted to the

conditions in which they live

■ observe the adaptations, eg body shape, of a rangeof organisms from different habitats

■ develop an understanding of the ways in whichadaptations enable organisms to survive

■ suggest the factors for which organisms arecompeting in a given habitat

■ evaluate data concerned with the effect ofenvironmental changes on the distributionand behaviour of living organisms.

B1.4.1 Adaptations

a) To survive and reproduce, organisms require asupply of materials from their surroundings andfrom the other living organisms there.

b) Plants often compete with each other for light andspace, and for water and nutrients from the soil.

c) Animals often compete with each other for food,mates and territory.

d) Organisms, including microorganisms, have features(adaptations) that enable them to survive in theconditions in which they normally live.

e) Some organisms live in environments that are veryextreme. Extremophiles may be tolerant to high levelsof salt, high temperatures or high pressures.


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Examination questions will use examples that areunfamiliar to candidates.


Factors are limited to light, water, space and nutrients inplants; and to food, mates and territory in animals.


Knowledge and understanding of the process ofeutrophication is not required.

Candidates should understand the use of equipment tomeasure oxygen levels, temperature and rainfall.


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Examples might include, but are not limited to, thechanging distribution of some bird species and thedisappearance of pollinating insects, including bees.

f) Animals and plants may be adapted for survival inthe conditions where they normally live, eg deserts,the Arctic.

Animals may be adapted for survival in dry and arcticenvironments by means of:

■ changes to surface area

■ thickness of insulating coat

■ amount of body fat

■ camouflage.

Plants may be adapted to survive in dry environmentsby means of:

■ changes to surface area, particularly of the leaves

■ water-storage tissues

■ extensive root systems.

g) Animals and plants may be adapted to cope with specificfeatures of their environment, eg thorns, poisons andwarning colours to deter predators.

B1.4.2 Environmental change

a) Changes in the environment affect the distributionof living organisms.

b) Animals and plants are subjected to environmentalchanges. Such changes may be caused by livingor non-living factors such as a change in acompetitor, or in the average temperature or rainfall.

c) Living organisms can be used as indicators of pollution:

■ lichens can be used as air pollution indicators,particularly of the concentration of sulfur dioxidein the atmosphere

■ invertebrate animals can be used as waterpollution indicators and are used as indicatorsof the concentration of dissolved oxygen in water.

d) Environmental changes can be measured usingnon-living indicators such as oxygen levels,temperature and rainfall.


■ investigations of environmental conditions and organisms in a habitat such as a pond

■ ‘hunt the cocktail stick’ using red and green cocktail sticks on a green background

■ investigate the distribution of European banded snails

■ investigate the behaviour of woodlice using choice chambers

■ investigate the effect on plant growth of varying their environmental conditions, eg degrees of shade, density ofsowing, supply of nutrients

■ investigating particulate levels, eg with the use of sensors to measure environmental conditions

■ the use of maximum–minimum thermometers, rainfall gauges and oxygen meters

■ investigating the effect of phosphate on oxygen levels in water using jars with algae, water and varyingnumbers of drops of phosphate, then monitor oxygen using a meter

■ computer simulations to model the effect on organisms of changes to the environment.

B1.5 Energy and biomass in food chains

By observing the numbers and sizes of the organisms in food chains we can find out what happens to energy andbiomass as it passes along the food chain.

Candidates should use their skills, knowledgeand understanding to:■ interpret pyramids of biomass and construct them

from appropriate information.

B1.5.1 Energy in biomass

a) Radiation from the Sun is the source of energy formost communities of living organisms. Green plantsand algae absorb a small amount of the light thatreaches them. The transfer from light energy tochemical energy occurs during photosynthesis.This energy is stored in the substances that makeup the cells of the plants.

b) The mass of living material (biomass) at each stagein a food chain is less than it was at the previousstage. The biomass at each stage can be drawnto scale and shown as a pyramid of biomass.


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An understanding of pyramids of number is notrequired.


Construction of food webs and chains, and of pyramidsof numbers, is not required.

c) The amounts of material and energy contained inthe biomass of organisms are reduced at eachsuccessive stage in a food chain because:

■ some materials and energy are always lost inthe organisms’ waste materials

■ respiration supplies all the energy needs forliving processes, including movement. Much ofthis energy is eventually transferred to thesurroundings.

B1.6 Waste materials from plants and animals

Many trees shed their leaves each year and most animals produce droppings at least once a day. All plants andanimals eventually die. Microorganisms play an important part in decomposing this material so that it can be usedagain by plants. The same material is recycled over and over again and can lead to stable communities.

Candidates should use their skills, knowledgeand understanding to:■ evaluate the necessity and effectiveness of schemes

for recycling organic kitchen or garden waste.

B1.6.1 Decay processes

a) Living things remove materials from the environmentfor growth and other processes. These materials arereturned to the environment either in waste materialsor when living things die and decay.

b) Materials decay because they are broken down(digested) by microorganisms. Microorganisms aremore active and digest materials faster in warm,moist, aerobic conditions.

c) The decay process releases substances that plantsneed to grow.

d) In a stable community, the processes that removematerials are balanced by processes that returnmaterials. The materials are constantly cycled.


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B1.6.2 The carbon cycle

a) The constant cycling of carbon is called thecarbon cycle.

In the carbon cycle:

■ carbon dioxide is removed from the environmentby green plants and algae for photosynthesis

■ the carbon from the carbon dioxide is used tomake carbohydrates, fats and proteins, whichmake up the body of plants and algae

■ when green plants and algae respire, some of thiscarbon becomes carbon dioxide and is releasedinto the atmosphere

■ when green plants and algae are eaten by animalsand these animals are eaten by other animals,some of the carbon becomes part of the fatsand proteins that make up their bodies

■ when animals respire, some of this carbonbecomes carbon dioxide and is released intothe atmosphere

■ when plants, algae and animals die, someanimals and microorganisms feed on their bodies

■ carbon is released into the atmosphere as carbondioxide when these organisms respire

■ by the time the microorganisms and detritusfeeders have broken down the waste productsand dead bodies of organisms in ecosystems andcycled the materials as plant nutrients, all theenergy originally absorbed by green plants andalgae has been transferred

■ combustion of wood and fossil fuels releasescarbon dioxide into the atmosphere.


■ design and carry out an investigation to measure the rate of decay of bread by, for example, exposing cubes ofbread to air before placing them in sealed Petri dishes at different temperatures and/or different moisture levels

■ investigate the rates of decay using containers (eg thermos flasks) full of grass clippings, one with disinfectant,one with dry grass, one with wet grass and one with a composting agent. If the container is sealed, athermometer or temperature probe can be placed through a cotton wool plug to monitor the temperature

■ potato decay competition, using fresh potatoes. Candidates decide on the environmental conditions and therate of decay is measured over a two week period

■ role play exercise – A4 sheets labelled with different stages of the carbon cycle. Candidates arrange themselvesin the correct order to pass a ball along labelled as carbon

■ using a sensor and data logger to investigate carbon dioxide levels during the decay process.


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B1.7 Genetic variation and its control

There are not only differences between different species of plants and animals but also between individuals of thesame species. These differences are due partly to the information in the cells they have inherited from their parentsand partly to the different environments in which the individuals live and grow. Asexual reproduction can be used toproduce individuals that are genetically identical to their parent. Scientists can now add, remove or change genesto produce the plants and animals they want.

Candidates should use their skills, knowledgeand understanding to:■ interpret information about cloning techniques and

genetic engineering techniques

■ make informed judgements about the economic, socialand ethical issues concerning cloning and geneticengineering, including genetically modified (GM) crops.

B1.7.1 Why organisms are different

a) The information that results in plants and animalshaving similar characteristics to their parents iscarried by genes, which are passed on in the sexcells (gametes) from which the offspring develop.

b) The nucleus of a cell contains chromosomes.Chromosomes carry genes that control thecharacteristics of the body.

c) Different genes control the development of differentcharacteristics of an organism.

d) Differences in the characteristics of differentindividuals of the same kind may be due todifferences in:

■ the genes they have inherited (genetic causes)

■ the conditions in which they have developed(environmental causes)

■ or a combination of both.


■ look at variation in leaf length or width, pod length, height. Compare plants growing in different conditions –sun/shade.




Candidates should understand that genes operate at amolecular level to develop characteristics that can beseen.

B1.7.2 Reproduction

a) There are two forms of reproduction:

■ sexual reproduction – the joining (fusion) of maleand female gametes. The mixture of the geneticinformation from two parents leads to variety inthe offspring

■ asexual reproduction – no fusion of gametes andonly one individual is needed as the parent. Thereis no mixing of genetic information and so nogenetic variation in the offspring. These geneticallyidentical individuals are known as clones.

b) New plants can be produced quickly and cheaply bytaking cuttings from older plants. These new plantsare genetically identical to the parent plant.

c) Modern cloning techniques include:

■ tissue culture – using small groups of cells frompart of a plant

■ embryo transplants – splitting apart cells from adeveloping animal embryo before they becomespecialised, then transplanting the identicalembryos into host mothers

■ adult cell cloning – the nucleus is removed froman unfertilised egg cell. The nucleus from an adultbody cell, eg a skin cell, is then inserted into theegg cell. An electric shock then causes the eggcell to begin to divide to form embryo cells. Theseembryo cells contain the same genetic informationas the adult skin cell. When the embryo hasdeveloped into a ball of cells, it is inserted intothe womb of an adult female to continueits development.

d) In genetic engineering, genes from the chromosomesof humans and other organisms can be ‘cut out’using enzymes and transferred to cells ofother organisms.


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e) Genes can also be transferred to the cells of animals,plants or microorganisms at an early stage in theirdevelopment so that they develop with desiredcharacteristics:

■ new genes can be transferred to crop plants

■ crops that have had their genes modified in thisway are called genetically modified crops (GM crops)

■ examples of genetically modified crops include onesthat are resistant to insect attack or to herbicides

■ genetically modified crops generally showincreased yields.

f) Concerns about GM crops include the effect onpopulations of wild flowers and insects, anduncertainty about the effects of eating GM cropson human health.


■ investigate the optimum conditions for the growth of cuttings, eg Mexican hat plants, spider plants, African violets

■ investigate the best technique for growing new plants from tissue cultures (eg cauliflower).

B1.8 Evolution

Particular genes or accidental changes in the genes of plants or animals may give them characteristics whichenable them to survive better. Over time this may result in entirely new species. There are different theories ofevolution. Darwin’s theory is the most widely accepted.

Candidates should use their skills, knowledgeand understanding to:■ interpret evidence relating to evolutionary theory

■ suggest reasons why Darwin’s theory of naturalselection was only gradually accepted

■ identify the differences between Darwin’s theory ofevolution and conflicting theories, such as thatof Lamarck

■ suggest reasons for the different theories.




Scientists may produce different hypotheses to explainsimilar observations. It is only when these hypothesesare investigated that data will support or refutehypotheses.


Candidates should understand how evolutionary trees(models) are used to represent the relationshipsbetween organisms.

Candidates should develop an understanding of thetimescales involved in evolution.


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A study of creationism is not required.

B1.8.1 Evolution

a) Darwin’s theory of evolution by natural selectionstates that all species of living things have evolvedfrom simple life forms that first developed more thanthree billion years ago.

b) The theory of evolution by natural selection was onlygradually accepted because:

■ the theory challenged the idea that God made allthe animals and plants that live on Earth

■ there was insufficient evidence at the time thetheory was published to convince many scientists

■ the mechanism of inheritance and variation wasnot known until 50 years after the theorywas published.

c) Other theories, including that of Lamarck, are basedmainly on the idea that changes that occur in anorganism during its lifetime can be inherited. We nowknow that in the vast majority of cases this type ofinheritance cannot occur.

d) Studying the similarities and differences betweenorganisms allows us to classify living organisms intoanimals, plants and microorganisms, and helps us tounderstand evolutionary and ecological relationships.Models allow us to suggest relationships betweenorganisms.

e) Evolution occurs via natural selection:

■ individual organisms within a particular speciesmay show a wide range of variation because ofdifferences in their genes

■ individuals with characteristics most suited to theenvironment are more likely to survive to breedsuccessfully

■ the genes that have enabled these individuals tosurvive are then passed on to the next generation.

f) Where new forms of a gene result from mutationthere may be relatively rapid change in a species ifthe environment changes.

3.4 Unit 2: Chemistry 1

Throughout this unit candidates will be expected to write word equations for reactions specified. Higher Tiercandidates will also be expected to write and balance symbol equations for reactions specified throughoutthe unit.

C1.1 The fundamental ideas in chemistry

Atoms and elements are the building blocks of chemistry. Atoms contain protons, neutrons and electrons. Whenelements react they produce compounds.

C1.1.1 Atoms

a) All substances are made of atoms. A substance that ismade of only one sort of atom is called an element.There are about 100 different elements. Elements areshown in the periodic table. The groups containelements with similar properties.

b) Atoms of each element are represented by achemical symbol, eg O represents an atom ofoxygen, and Na represents an atom of sodium.

c) Atoms have a small central nucleus, which ismade up of protons and neutrons and aroundwhich there are electrons.

d) The relative electrical charges are as shown:

Name of particle ChargeProton +1Neutron 0Electron –1

e) In an atom, the number of electrons is equal tothe number of protons in the nucleus. Atoms haveno overall electrical charge.

f) All atoms of a particular element have the samenumber of protons. Atoms of different elementshave different numbers of protons.

g) The number of protons in an atom of an element isits atomic number. The sum of the protons andneutrons in an atom is its mass number.


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Candidates should understand where metals andnon-metals appear in the periodic table.


Knowledge of the chemical symbols for elements otherthan those named in the specification is not required.


Candidates will be expected to calculate the number ofeach sub-atomic particle in an atom from its atomicnumber and mass number.


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Knowledge is limited to the reactions of Group 1elements with water and oxygen.

Candidates are not required to know of trends withineach group in the periodic table, but should be awareof similarities between the elements within a group.

Candidates should know that the noble gases haveeight electrons in their outer energy level, except forhelium, which has only two electrons.


Further details of the types of bonding are not required.

Candidates should know that metals lose electrons toform positive ions, whereas non-metals gain electrons toform negative ions. Knowledge of such transfers islimited to single electrons.

Candidates should be able to write word equations forreactions in the specification. The ability to interpretgiven symbol equations in terms of numbers of atoms isrequired.

Higher Tier candidates should be able to balancesymbol equations.

Knowledge and understanding of masses in chemicalreactions is limited to conservation of mass. Calculationsbased on relative atomic masses are not required butcandidates should be able to calculate the mass of areactant or product from information about the massesof the other reactants and products in the reaction.


Candidates should be able to represent the electronicstructure of the first 20 elements of the periodic table inthe following forms:

sodium2,8,1

h) Electrons occupy particular energy levels. Each electronin an atom is at a particular energy level (in a particularshell). The electrons in an atom occupy the lowestavailable energy levels (innermost available shells).Candidates may answer questions in terms of eitherenergy levels or shells.

C1.1.2 The periodic table

a) Elements in the same group in the periodic tablehave the same number of electrons in their highestenergy level (outer electrons) and this gives themsimilar chemical properties.

b) The elements in Group 0 of the periodic table arecalled the noble gases. They are unreactive becausetheir atoms have stable arrangements of electrons.

C1.1.3 Chemical reactions

a) When elements react, their atoms join with otheratoms to form compounds. This involves giving,taking or sharing electrons to form ions or molecules.Compounds formed from metals and non-metalsconsist of ions. Compounds formed from non-metalsconsist of molecules. In molecules the atoms areheld together by covalent bonds.

b) Chemical reactions can be represented by wordequations or by symbol equations.

c) No atoms are lost or made during a chemicalreaction so the mass of the products equalsthe mass of the reactants.


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Candidates should know that limestone is needed forbuildings and that the positive benefits of using thismaterial should be considered against the negativeaspects of quarrying.

Knowledge of building materials is limited to limestone,cement and concrete.

Knowledge of particular developments is not required,but information may be supplied in examinationquestions for candidates to evaluate.

Knowledge of the properties of other building materialsis not required, but candidates may be provided withinformation about materials such as timber, stone, glassand steels in the examination so that they can makecomparisons about their uses.


Knowledge and understanding of metal carbonates islimited to metal carbonates decomposing on heating togive carbon dioxide and the metal oxide.

Candidates should be aware that not all carbonates ofmetals in Group 1 of the periodic table decompose atthe temperatures reached by a Bunsen burner.

Knowledge of the common names quicklime andslaked lime is not required.


■ modelling of atoms (using physical models or computer simulations) to illustrate chemical reactions at theatomic level

■ precipitation reactions, such as lead nitrate with potassium iodide, to show conservation of mass.

C1.2 Limestone and building materials

Rocks provide essential building materials. Limestone is a naturally occurring resource that provides a startingpoint for the manufacture of cement and concrete.

Candidates should use their skills, knowledgeand understanding to:■ consider and evaluate the environmental, social and

economic effects of exploiting limestone andproducing building materials from it

■ evaluate the developments in using limestone,cement and concrete as building materials, andtheir advantages and disadvantages over othermaterials.

C1.2.1 Calcium carbonate

a) Limestone, mainly composed of the compoundcalcium carbonate (CaCO3), is quarried and canbe used as a building material.

b) Calcium carbonate can be decomposed byheating (thermal decomposition) to make calciumoxide and carbon dioxide.

c) The carbonates of magnesium, copper, zinc,calcium and sodium decompose on heating ina similar way.

d) Calcium oxide reacts with water to produce calciumhydroxide, which is an alkali that can be used in theneutralisation of acids.


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Candidates should know that metal ores are obtainedby mining and that this may involve digging up andprocessing large amounts of rock.

Knowledge and understanding of obtaining, using andrecycling metals is limited to the metals named in thesubject content.

Knowledge and understanding of the uses andproperties of metals and alloys is limited to thosespecified in the subject content. Information may begiven in examination questions so that candidates canevaluate their uses.


Candidates should be familiar with using limewater totest for carbon dioxide gas.

The reaction of carbonates with acids is limited to thereactions of magnesium, copper, zinc, calcium andsodium.

e) A solution of calcium hydroxide in water (limewater)reacts with carbon dioxide to produce calciumcarbonate. Limewater is used as a test for carbondioxide. Carbon dioxide turns limewater cloudy.

f) Carbonates react with acids to produce carbondioxide, a salt and water. Limestone is damagedby acid rain.

g) Limestone is heated with clay to make cement.Cement is mixed with sand to make mortar andwith sand and aggregate to make concrete.


■ investigation of the limestone cycle: decomposition of CaCO3 to give CaO, reaction with water to giveCa(OH)2, addition of more water and filtering to give limewater and use of limewater to test for CO2

■ thermal decomposition of CaCO3 to show limelight

■ honeycomb demonstration: heat sugar syrup mixture to 150°C and add sodium bicarbonate

■ making concrete blocks in moulds, investigation of variation of content and carrying out strength tests

■ design and carry out an investigation of trends in the thermal decomposition of metal carbonates

■ investigation of the reaction of carbonates with acids.

C1.3 Metals and their uses

Metals are very useful in our everyday lives. Ores are naturally occurring rocks that provide an economic startingpoint for the manufacture of metals. Iron ore is used to make iron and steel. Copper can be easily extracted butcopper-rich ores are becoming scarce so new methods of extracting copper are being developed. Aluminium andtitanium are useful metals but are expensive to produce. Metals can be mixed together to make alloys.

Candidates should use their skills, knowledgeand understanding to:■ consider and evaluate the social, economic and

environmental impacts of exploiting metal ores, ofusing metals and of recycling metals

■ evaluate the benefits, drawbacks and risks ofusing metals as structural materials.


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Knowledge of specific examples is not required. Datamay be provided in examination questions forcandidates to analyse.

Knowledge of specific examples other than those givenbelow is not required.


Knowledge and understanding is limited to thereduction of oxides using carbon.

Knowledge of reduction is limited to the removal ofoxygen.

Knowledge of the details of the extraction of othermetals is not required. Examination questions mayprovide further information about specific processes forcandidates to interpret or evaluate.

Details of the blast furnace are not required.

Knowledge of the details of industrial methods ofelectrolysis is not required.

Details of industrial smelting processes are notrequired.

Candidates should know that:

■ copper is extracted from its ores by chemicalprocesses that involve heat or electricity

■ copper-rich ores are being depleted and traditionalmining and extraction have major environmentalimpacts.

C1.3.1 Extracting metals

a) Ores contain enough metal to make it economic toextract the metal. The economics of extractionmay change over time.

b) Ores are mined and may be concentrated before themetal is extracted and purified.

c) Unreactive metals such as gold are found in the Earthas the metal itself, but most metals are found ascompounds that require chemical reactions toextract the metal.

d) Metals that are less reactive than carbon can beextracted from their oxides by reduction withcarbon, for example iron oxide is reduced in theblast furnace to make iron.

e) Metals that are more reactive than carbon, such asaluminium, are extracted by electrolysis of moltencompounds. The use of large amounts of energyin the extraction of these metals makes themexpensive.

f) Copper can be extracted from copper-rich ores byheating the ores in a furnace (smelting). The coppercan be purified by electrolysis. The supply ofcopper-rich ores is limited.


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Candidates should know and understand that:

■ phytomining uses plants to absorb metalcompounds and that the plants are burned toproduce ash that contains the metal compounds

■ bioleaching uses bacteria to produce leachatesolutions that contain metal compounds.

Further specific details of these processes are notrequired.

Candidates should know that during electrolysispositive ions move towards the negative electrode.They do not need to describe this in terms of oxidationand reduction, or to understand half equations.

Candidates do not need to know the details ofmethods used to extract these metals, but should beable to comment on and evaluate information that isgiven about the chemical processes that can be used.

Candidates are not required to know details of specificexamples of recycling, but should understand thebenefits of recycling in the general terms specified here.


Knowledge of uses of blast furnace iron is limited toblast furnace iron being used as cast iron because of itsstrength in compression.

Knowledge and understanding of the types of steel andtheir properties is limited to those specified in thesubject content. Information about the composition ofspecific types of steel may be given in examinationquestions so that candidates can evaluate their uses.

Candidates should be familiar with these specifiedexamples but examination questions may containinformation about alloys other than those named in thesubject content to enable candidates to makecomparisons.

g) New ways of extracting copper from low-grade ores are being researched to limit the environmentalimpact of traditional mining.

Copper can be extracted by phytomining, or bybioleaching.

h) Copper can be obtained from solutions of coppersalts by electrolysis or by displacement usingscrap iron.

i) Aluminium and titanium cannot be extracted fromtheir oxides by reduction with carbon. Currentmethods of extraction are expensive because:

■ there are many stages in the processes

■ large amounts of energy are needed.

j) We should recycle metals because extracting themuses limited resources and is expensive in termsof energy and effects on the environment.

C1.3.2 Alloys

a) Iron from the blast furnace contains about 96%iron. The impurities make it brittle and so it haslimited uses.

b) Most iron is converted into steels. Steels are alloyssince they are mixtures of iron with carbon. Somesteels contain other metals. Alloys can be designedto have properties for specific uses. Low-carbonsteels are easily shaped, high-carbon steels arehard, and stainless steels are resistant to corrosion.

c) Most metals in everyday use are alloys. Pure copper,gold, iron and aluminium are too soft for many usesand so are mixed with small amounts of similarmetals to make them harder for everyday use.


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Knowledge of the properties of specific transition metalsother than those named in this unit is not required.

Candidates should know and understand that copper:

■ is a good conductor of electricity and heat

■ can be bent but is hard enough to be used to makepipes or tanks

■ does not react with water.

C1.3.3 Properties and uses of metals

a) The elements in the central block of the periodictable are known as transition metals. Like othermetals they are good conductors of heat andelectricity and can be bent or hammered intoshape. They are useful as structural materialsand for making things that must allow heat orelectricity to pass through them easily.

b) Copper has properties that make it usefulfor electrical wiring and plumbing.

c) Low density and resistance to corrosion makealuminium and titanium useful metals.


■ comparing less reactive metals (gold, silver, copper) with more reactive metals, eg in acid

■ heating metal oxides with carbon to compare reactivity, eg CuO, PbO, Fe2O3

■ heating copper carbonate with charcoal to produce copper

■ displacement reactions, eg CuSO4(aq) + Fe (using temperature sensors to investigate differences in metalreactivity)

■ investigation of the physical properties of metals and alloys, eg density / thermal and electrical conductivity

■ electrolysis of copper sulfate solution using copper electrodes

■ ignition tube demonstration of blast furnace – potassium permanganate, mineral wool plug, iron oxide mixedwith carbon

■ investigation of phytomining: growing brassica plants in compost with added copper sulfate or sprayingbrassica plants (eg cabbage leaves) with copper sulfate solution, ashing the plants (fume cupboard), addingsulfuric acid to the ash, filtering and obtaining the metal from the solution by displacement or electrolysis.


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Knowledge and understanding of the products ofburning hydrocarbon fuels and the effects of theseproducts is limited to those named in the subjectcontent for this section.

Candidates may be given information and data aboutother fuels and their products of combustion forcomparison and evaluation in the examinations.

Candidates should know and understand the benefitsand disadvantages of ethanol and hydrogen as fuels interms of:

■ use of renewable resources

■ storage and use of the fuels

■ their products of combustion.


Candidates are not expected to know the names ofspecific alkanes other than methane, ethane andpropane.

C1.4 Crude oil and fuels

Crude oil is derived from an ancient biomass found in rocks. Many useful materials can be produced from crudeoil. Crude oil can be fractionally distilled. Some of the fractions can be used as fuels. Biofuels are produced fromplant material. There are advantages and disadvantages to their use as fuels. Fuels can come from renewable ornon-renewable resources.

Candidates should use their skills, knowledgeand understanding to:■ evaluate the impact on the environment of burning

hydrocarbon fuels

■ consider and evaluate the social, economic andenvironmental impacts of the uses of fuels

■ evaluate developments in the production and usesof better fuels, for example ethanol and hydrogen

■ evaluate the benefits, drawbacks and risks ofusing plant materials to produce fuels.

C1.4.1 Crude oil

a) Crude oil is a mixture of a very large numberof compounds.

b) A mixture consists of two or more elements orcompounds not chemically combined together.The chemical properties of each substance inthe mixture are unchanged. It is possible toseparate the substances in a mixture byphysical methods including distillation.

c) Most of the compounds in crude oil consist ofmolecules made up of hydrogen and carbonatoms only (hydrocarbons). Most of these aresaturated hydrocarbons called alkanes, whichhave the general formula CnH2n+2.


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3Candidates should know and understand the mainprocesses in continuous fractional distillation in afractionating column.

Knowledge of the names of specific fractions or fuels isnot required.

Knowledge of trends in properties of hydrocarbons islimited to:

■ boiling points

■ viscosity

■ flammability.


Candidates should be able to recognise alkanes fromtheir formulae in any of the forms but do not need toknow the names of individual alkanes other thanmethane, ethane, propane and butane.

Candidates should know that in displayed structures —represents a covalent bond.


Candidates should be able to relate products ofcombustion to the elements present in compounds inthe fuel and to the extent of combustion (whethercomplete or partial).

No details of how the oxides of nitrogen are formed arerequired, other than the fact that they are formed athigh temperatures.

Solid particles may contain soot (carbon) and unburntfuels.

C1.4.2 Hydrocarbons

a) Alkane molecules can be represented in thefollowing forms:

■ C2H6

H HI I

■ H –– C –– C –– HI IH H

b) The many hydrocarbons in crude oil may beseparated into fractions, each of which containsmolecules with a similar number of carbon atoms,by evaporating the oil and allowing it to condenseat a number of different temperatures. This processis fractional distillation.

c) Some properties of hydrocarbons depend on thesize of their molecules. These properties influencehow hydrocarbons are used as fuels.

C1.4.3 Hydrocarbon fuels

a) Most fuels, including coal, contain carbon and / orhydrogen and may also contain some sulfur.The gases released into the atmosphere whena fuel burns may include carbon dioxide, water(vapour), carbon monoxide, sulfur dioxide andoxides of nitrogen. Solid particles (particulates)may also be released.

b) The combustion of hydrocarbon fuels releasesenergy. During combustion the carbon andhydrogen in the fuels are oxidised.


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Candidates are not required to know details of anyother causes of acid rain or global warming.

Knowledge of the methods of removing sulfur is notrequired.

Knowledge of the methods of biofuel production is notrequired but candidates may be given information fromwhich a range of questions may be asked.

c) Sulfur dioxide and oxides of nitrogen cause acid rain,carbon dioxide causes global warming, and solidparticles cause global dimming.

d) Sulfur can be removed from fuels before they areburned, for example in vehicles. Sulfur dioxide canbe removed from the waste gases after combustion,for example in power stations.

e) Biofuels, including biodiesel and ethanol, areproduced from plant material. There are economic,ethical and environmental issues surroundingtheir use.


■ demonstration of fractional distillation of crude oil using CLEAPSS mixture (take care to avoid confusion withthe continuous process in a fractionating column)

■ design an investigation on viscosity, ease of ignition or sootiness of flame of oils or fuels

■ comparison of the energy content of different fuels, for example by heating a fixed volume of water

■ demonstration of the production of solid particles by incomplete combustion using a Bunsen burner yellowflame or a candle flame to boil a tube of cold water

■ collecting and testing the products of combustion of candle wax and methane

■ demonstration of burning sulfur or coal in oxygen and then testing the pH of the gas produced

■ design an investigation on growing cress from seeds in various concentrations of sodium metabisulfite solutionto show how acid rain affects plants.


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Candidates should be aware that crude oil is used toproduce fuels and chemicals, and that it is a limitedresource.

Candidates should be able to evaluate informationabout the ways in which crude oil and its products areused. Although candidates will probably know thenames of some common polymers, these are notrequired knowledge, unless they are included in thesubject content for this section.


Candidates should be able to compare theenvironmental impact of producing ethanol fromrenewable and non-renewable sources.


Candidates should be able to recognise alkenes from theirnames or formulae, but do not need to know the namesof individual alkenes, other than ethene and propene.

Candidates should know that in displayed structures== represents a double bond.

C1.5 Other useful substances from crude oil

Fractions from the distillation of crude oil can be broken down (cracked) to make smaller molecules includingunsaturated hydrocarbons such as ethene. Unsaturated hydrocarbons can be used to make polymers and ethenecan be used to make ethanol. Ethanol can also be made by fermentation.

Candidates should use their skills, knowledgeand understanding to:■ evaluate the social and economic advantages and

disadvantages of using products from crude oil asfuels or as raw materials for plastics and otherchemicals

■ evaluate the social, economic and environmentalimpacts of the uses, disposal and recycling of polymers

■ evaluate the advantages and disadvantages of makingethanol from renewable and non-renewable sources.

C1.5.1 Obtaining useful substances from crude oil

a) Hydrocarbons can be cracked to produce smaller, more useful molecules. This process involves heating thehydrocarbons to vaporise them. The vapours are eitherpassed over a hot catalyst or mixed with steam andheated to a very high temperature so that thermaldecomposition reactions then occur.

b) The products of cracking include alkanes andunsaturated hydrocarbons called alkenes. Alkeneshave the general formula CnH2n.

c) Unsaturated hydrocarbon molecules can berepresented in the following forms:

■ C3H6

H H HI I I

■ H –– C –– C == CI IH H


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Candidates should be able to recognise the moleculesinvolved in these reactions in the forms shown in thesubject content. They should be able to represent theformation of a polymer from a given alkene monomer.

Further details of polymerisation are not required.

Candidates should consider the ways in which newmaterials are being developed and used, but will notneed to recall the names of specific examples.

Knowledge of specific named examples is not required,but candidates should be aware of the problems thatare caused by landfill sites and by litter.


No further details of these processes are required.

d) Alkenes react with bromine water, turning itfrom orange to colourless.

e) Some of the products of cracking are useful as fuels.

C1.5.2 Polymers

a) Alkenes can be used to make polymers such aspoly(ethene) and poly(propene). In these reactions,many small molecules (monomers) join together toform very large molecules (polymers).For example:

H H H HI I I I

n C C C CI I I IH H H H n

ethene poly(ethene)

b) Polymers have many useful applications and newuses are being developed, for example: newpackaging materials, waterproof coatings forfabrics, dental polymers, wound dressings,hydrogels, smart materials (including shapememory polymers).

c) Many polymers are not biodegradable, so they arenot broken down by microbes and this can lead toproblems with waste disposal.

d) Plastic bags are being made from polymers andcornstarch so that they break down more easily.Biodegradable plastics made from cornstarchhave been developed.

C1.5.3 Ethanol

a) Ethanol can be produced by the hydration ofethene with steam in the presence of a catalyst.

b) Ethanol can also be produced by fermentationwith yeast, using renewable resources.This can be represented by:

sugar carbon dioxide + ethanol


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Knowledge is limited to the high-energy content ofvegetable oils, the possible health benefits ofunsaturated fats compared with saturated fats, and theeffects of cooking foods in oil. Information may beprovided in examinations for candidates to evaluate.

Candidates do not need to recall the names of specificadditives.

Further information will be provided in questions forevaluation and comparison.


Candidates should study the general principles of theextraction of vegetable oils, such as olive oil, rapeseedoil or lavender oil.

Knowledge of specific examples or processes is notrequired.

Knowledge of the details of the production of biodieselis not required.

Knowledge of specific nutrients is not required.


■ demonstration of the cracking of liquid paraffin using broken pottery as the catalyst

■ testing for unsaturation in the alkenes using bromine water

■ making a polymer from cornstarch

■ demonstration of making Perspex

■ molecular modelling of polymers

■ design an investigation of a property of different plastics, eg strength, flexibility, biodegradability

■ investigate the amount of water that can be absorbed by a hydrogel (eg those used as additives to gardencomposts)

■ testing coated fabrics for water penetration.

C1.6 Plant oils and their uses

Many plants produce useful oils that can be converted into consumer products including processed foods.Emulsions can be made and have a number of uses. Vegetable oils can be hardened to make margarine.Biodiesel fuel can be produced from vegetable oils.

Candidates should use their skills, knowledgeand understanding to:■ evaluate the effects of using vegetable oils in foods

and the impacts on diet and health

■ evaluate the use, benefits, drawbacks and risks ofemulsifiers in foods.

C1.6.1 Vegetable oils

a) Some fruits, seeds and nuts are rich in oils that canbe extracted. The plant material is crushed and theoil is removed by pressing or in some cases bydistillation. Water and other impurities are removed.

b) Vegetable oils are important foods and fuels as theyprovide a lot of energy. They also provide us withnutrients.


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Candidates should study how emulsions are made andshould understand the role of emulsifiers in producingemulsions that are more stable. Knowledge of specificnames of ingredients in proprietary products is notrequired.

HT only

Knowledge is limited to a simple model of thestructure of emulsifier molecules.


Candidates should be familiar with a test forunsaturation using bromine water.

HT only

Candidates should know how and why vegetableoils are hardened for use in foods. Knowledge oftrans fats is not required.

Examination questions may provide furtherinformation from which candidates may be askedto make comparisons.

c) Vegetable oils have higher boiling points than waterand so can be used to cook foods at highertemperatures than by boiling. This produces quickercooking and different flavours but increases theenergy that the food releases when it is eaten.

C1.6.2 Emulsions

a) Oils do not dissolve in water. They can be used toproduce emulsions. Emulsions are thicker than oilor water and have many uses that depend on theirspecial properties. They provide better texture,coating ability and appearance, for example insalad dressings, ice creams, cosmetics and paints.

b) Emulsifiers have hydrophilic and hydrophobicproperties.

C1.6.3 Saturated and unsaturated oils

a) Vegetable oils that are unsaturated contain doublecarbon–carbon bonds. These can be detected byreacting with bromine water.

b) Vegetable oils that are unsaturated can behardened by reacting them with hydrogen inthe presence of a nickel catalyst at about 60°C.Hydrogen adds to the carbon–carbon doublebonds. The hydrogenated oils have highermelting points so they are solids at roomtemperature, making them useful as spreadsand in cakes and pastries.


■ pressing nuts (eg walnuts) between paper towels and studying the grease marks

■ steam distillation of lavender oil, orange oil, lemon oil, olive oil, rapeseed oil or vegetable oil

■ simple calorimetry investigations using small spirit burners or bottle tops to measure the energy released fromvarious oils (weigh before and after, and measure the temperature change for a known mass of water)

■ making emulsions, eg oil /water, oil /vinegar

■ investigating the effect of emulsifiers on the stability of emulsions

■ using bromine water to test fats and oils for unsaturation, eg testing sunflower oil against butter (usingcolorimeter to measure level of unsaturation).


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Candidates should have studied accounts ofWegener’s work. Knowledge is limited to the theoriesrelating to mountain building and continental drift.

Candidates should know that scientists once thoughtthat the features of the Earth’s surface were the result ofthe shrinking of the crust as the Earth cooled downfollowing its formation.

Candidates may be given information which they will beexpected to interpret.

Candidates should be able to compare and evaluatedifferent theories when given suitable information.

Knowledge of the effects of human activities is limitedto those in the subject content.

HT only


Knowledge is limited to the names of the three majorparts, and an awareness of the relative sizes of thesefeatures.

Knowledge of the names, shapes or locations ofspecific plates is not required.

Candidates should know that the mantle is mostlysolid, but that it is able to move slowly.

C1.7 Changes in the Earth and its atmosphere

The Earth and its atmosphere provide everything we need. The Earth has a layered structure. The surface of theEarth and its atmosphere have changed since the Earth was formed and are still changing. The atmosphere hasbeen much the same for the last 200 million years and provides the conditions needed for life on Earth. Recentlyhuman activities have resulted in further changes in the atmosphere. There is more than one theory about how lifewas formed.

Candidates should use their skills, knowledgeand understanding to:■ recognise that the Earth’s crust, the atmosphere and

the oceans are the only source of minerals and otherresources that humans need

■ explain why Wegener’s theory of crustal movement(continental drift) was not generally accepted formany years

■ explain why scientists cannot accurately predictwhen earthquakes and volcanic eruptions will occur

■ explain and evaluate theories of the changes thathave occurred and are occurring in the Earth’satmosphere

■ explain and evaluate the effects of human activitieson the atmosphere

■ describe why we do not know how life was firstformed.

C1.7.1 The Earth’s crust

a) The Earth consists of a core, mantle and crust, andis surrounded by the atmosphere.

b) The Earth’s crust and the upper part of the mantleare cracked into a number of large pieces(tectonic plates).

c) Convection currents within the Earth’s mantle drivenby heat released by natural radioactive processescause the plates to move at relative speeds of a fewcentimetres per year.


No knowledge of other theories is required. Informationmay be given in questions which candidates will beexpected to interpret.


HT only

Candidates should be aware of the Miller Ureyexperiment and the ‘primordial soup’ theory, butthey should know that this is not the only theory.

Candidates should be aware that plants and algaeproduce oxygen by a process called photosynthesisand that this process uses carbon dioxide from theatmosphere.

Knowledge of the process of photosynthesis is notrequired.


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Knowledge of the changes that occur at plateboundaries is limited to earthquakes and volcaniceruptions.

Knowledge of the mechanism of these changes is notrequired.

d) The movements can be sudden and disastrous.Earthquakes and / or volcanic eruptions occur atthe boundaries between tectonic plates.

C1.7.2 The Earth’s atmosphere

a) For 200 million years, the proportions of differentgases in the atmosphere have been much thesame as they are today:

■ about four-fifths (80%) nitrogen

■ about one-fifth (20%) oxygen

■ small proportions of various other gases, includingcarbon dioxide, water vapour and noble gases.

b) During the first billion years of the Earth’s existencethere was intense volcanic activity. This activityreleased the gases that formed the early atmosphereand water vapour that condensed to form the oceans.

c) There are several theories about how theatmosphere was formed.

One theory suggests that during this period theEarth’s atmosphere was mainly carbon dioxide andthere would have been little or no oxygen gas(like the atmospheres of Mars and Venus today).There may also have been water vapour and smallproportions of methane and ammonia.

d) There are many theories as to how life was formedbillions of years ago.

e) One theory as to how life was formed involvesthe interaction between hydrocarbons,ammonia and lightning.

f) Plants and algae produced the oxygen that is nowin the atmosphere.


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Candidates should know that carbon dioxide dissolvesin the oceans and that limestone was formed from theshells and skeletons of marine organisms. Fossil fuelscontain carbon and hydrocarbons that are the remainsof plants and animals.


Candidates should be aware that this increase incarbon dioxide is thought to be causing global warmingbut, for this unit, candidates do not need to know howCO2 causes this effect.

HT only

Knowledge of the boiling points of the differentgases is not required.

g) Most of the carbon from the carbon dioxide in theair gradually became locked up in sedimentaryrocks as carbonates and fossil fuels.

h) The oceans also act as a reservoir for carbondioxide but increased amounts of carbon dioxideabsorbed by the oceans has an impact on themarine environment.

i) Nowadays the release of carbon dioxide by burningfossil fuels increases the level of carbon dioxide inthe atmosphere.

j) Air is a mixture of gases with different boilingpoints and can be fractionally distilled toprovide a source of raw materials used in avariety of industrial processes.


■ investigating the composition of air by passing air over heated copper using gas syringes and measuring thepercentage of oxygen. Then burning magnesium in the nitrogen to form Mg3N2. Add water to produceammonia (nitrogen must have come from the air)

■ collecting gas produced by aquatic plants and testing for oxygen (using dissolved oxygen sensor)

■ measuring the amount of carbon dioxide in inhaled and exhaled air (using carbon dioxide sensor)

■ testing the products of combustion of fuels to show that carbon dioxide is produced

■ design an investigation to compare the amount of carbon dioxide released by reacting crushed shells(eg cockle, oyster) with dilute hydrochloric acid.


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Examples should include the design of a vacuum flask,how to reduce the energy transfer from a building andhow humans and animals cope with low temperatures.

Examples include radiators and heat sinks.

Examples include loft insulation and cavity wallinsulation.

Examples include the use of water, which has a veryhigh specific heat capacity, oil-filled radiators andelectric storage heaters containing concrete or bricks.

3.5 Unit 3: Physics 1

P1.1 The transfer of energy by heating processes and the factors that affect the rate at whichthat energy is transferred

Energy can be transferred from one place to another by work or by heating processes. We need to know how thisenergy is transferred and which heating processes are most important in a particular situation.

Candidates should use their skills, knowledgeand understanding to:■ compare ways in which energy is transferred in and

out of objects by heating and ways in which therates of these transfers can be varied

■ evaluate the design of everyday appliances thattransfer energy by heating, including economicconsiderations

■ evaluate the effectiveness of different types of materialused for insulation, including U-values and economicfactors including payback time

■ evaluate different materials according to their specificheat capacities.

P1.1.1 Infrared radiation

a) All objects emit and absorb infrared radiation.

b) The hotter an object is the more infrared radiation itradiates in a given time.

c) Dark, matt surfaces are good absorbers and goodemitters of infrared radiation.

d) Light, shiny surfaces are poor absorbers and pooremitters of infrared radiation.

e) Light, shiny surfaces are good reflectors of infraredradiation.


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Candidates should understand in simple terms how thearrangement and movement of particles determinewhether a material is a conductor or an insulator.

Candidates should understand the role of free electronsin conduction through a metal.

Candidates should be able to use the idea of particlesmoving apart to make a fluid less dense, to explainsimple applications of convection.

Candidates should be able to explain evaporation andthe cooling effect this causes using the kinetic theory.

Candidates should be able to explain the design ofdevices in terms of energy transfer, for example, coolingfins.

Candidates should be able to explain animaladaptations in terms of energy transfer, for example,relative ear size of animals in cold and warm climates.


Candidates should be able to recognise simplediagrams to model the difference between solids,liquids and gases.

An understanding of specific latent heat is not required.

P1.1.2 Kinetic theory

a) The use of kinetic theory to explain the differentstates of matter.

b) The particles of solids, liquids and gases havedifferent amounts of energy.

P1.1.3 Energy transfer by heating

a) The transfer of energy by conduction, convection,evaporation and condensation involves particles,and how this transfer takes place.

b) The factors that affect the rate of evaporation andcondensation.

c) The rate at which an object transfers energy byheating depends on:

■ surface area and volume

■ the material from which the object is made

■ the nature of the surface with which the object isin contact.

d) The bigger the temperature difference between anobject and its surroundings, the faster the rate atwhich energy is transferred by heating.

P1.1.4 Heating and insulating buildings

a) U-values measure how effective a material is asan insulator.

b) The lower the U-value, the better the material is asan insulator.

c) Solar panels may contain water that is heated byradiation from the Sun. This water may then be usedto heat buildings or provide domestic hot water.

d) The specific heat capacity of a substance is theamount of energy required to change thetemperature of one kilogram of the substanceby one degree Celsius.

E � m � c � �


■ passing white light through a prism and detecting the infrared radiation with a thermometer

■ demonstration using balls in a tray to show the behaviour of particles in substances in different states

■ measuring the cooling effect produced by evaporation: putting wet cotton wool over the bulb of a thermometeror temperature probe

■ plan and carry out an investigation into factors that affect the rate of cooling of a can of water, eg shape,volume, and colour of can

■ using Leslie’s cube to demonstrate the effect on radiation of altering the nature of the surface

■ plan and carry out an investigation using immersion heaters in a metal block to measure specific heat capacity

■ investigating thermal conduction using rods of different materials.


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Knowledge of the U-values of specific materials is notrequired, nor is the equation that defines a U-value.


E is energy transferred in joules, J

m is mass in kilograms, kg

� is temperature change in degrees Celsius, °C

c is specific heat capacity in J / kg °C


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The term ‘payback time’ should be understood.

Given relevant data, candidates should be able to makejudgements about the cost effectiveness of differentmethods of reducing energy consumption over a setperiod of time. This is not restricted to a considerationof building insulation but may include:

■ low energy light bulbs and LED lighting

■ replacing old appliances with energy efficient ones

■ ways in which ‘waste’ energy can be useful, egheat exchangers.

Common electrical appliances found in the home willbe examined. Examples will not be limited to electricalappliances; however, in this case all the informationwould be given in the question.

Candidates should be able to use a Sankey diagram tocalculate the efficiency of an appliance.

P1.2 Energy and efficiency

Appliances transfer energy but they rarely transfer all of the energy to the place we want. We need to know theefficiency of appliances so that we can choose between them, including how cost effective they are, and try toimprove them.

Candidates should use their skills, knowledgeand understanding to:■ compare the efficiency and cost effectiveness of

methods used to reduce ‘energy consumption’

■ describe the energy transfers and the main energywastages that occur with a range of appliances

■ interpret and draw a Sankey diagram.

P1.2.1 Energy transfers and efficiency

a) Energy can be transferred usefully, stored, ordissipated, but cannot be created or destroyed.

b) When energy is transferred, only part of it may beusefully transferred; the rest is ‘wasted’.

c) Wasted energy is eventually transferred to thesurroundings, which become warmer. The wastedenergy becomes increasingly spread out and sobecomes less useful.


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Candidates will not be required to convert betweenkilowatt-hours and joules.E is energy transferred in kilowatt-hours, kWhP is power in kilowatts, kWt is time in hours, h

This equation may also be used when:E is energy transferred in joules, JP is power in watts, Wt is time in seconds, s

This includes both the cost of using individualappliances and the interpretation of electricity meterreadings to calculate total cost over a period of time.


Candidates will be required to compare differentelectrical appliances, using data provided.


Candidates may be required to calculate efficiency as adecimal or as a percentage.

d) To calculate the efficiency of a device using:

efficiency �useful energy out

(�100%)total energy in

efficiency �useful power out

(�100%)total power in


■ an energy ‘circus’ to demonstrate various energy transfers

■ plan and carry out an investigation by constructing a model house, using sensors and data logger to measuretemperatures with and without various types of insulation.

P1.3 The usefulness of electrical appliances

We often use electrical appliances because they transfer energy at the flick of a switch. We can calculate howmuch energy is transferred by an appliance and how much the appliance costs to run.

Candidates should use their skills, knowledgeand understanding to:■ compare the advantages and disadvantages of using

different electrical appliances for a particularapplication

■ consider the implications of instances whenelectricity is not available.

P1.3.1 Transferring electrical energy

a) Examples of energy transfers that everyday electricalappliances are designed to bring about.

b) The amount of energy an appliance transfersdepends on how long the appliance is switchedon and its power.

c) To calculate the amount of energy transferredfrom the mains using:

E � P � t

d) To calculate the cost of mains electricity given thecost kilowatt-hour.


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Candidates should be able to evaluate differentmethods of generating electricity given data includingstart-up times, costs of electricity generation and thetotal cost of generating electricity, when factors such asbuilding and decommissioning are taken into account.The reliability of different methods should also beunderstood.

Knowledge of the actual values of start-up times andwhy they are different is not needed, but theimplications of such differences are important.

Candidates should be aware of the fact that, of thefossil fuel power stations, gas-fired have the shorteststart-up time. They should also be aware of theadvantages of pumped storage systems in order tomeet peak demand, and as a means of storing energyfor later use.


■ candidates reading the electricity meter at home on a daily or weekly basis. They could then look for trends inusage and try to explain these, eg in terms of weather conditions

■ plan and carry out an investigation using an electrical joulemeter to measure the energy transferred by lowvoltage bulbs of different powers, low voltage motors and low voltage immersion heaters.

P1.4 Methods we use to generate electricity

Various energy sources can be used to generate the electricity we need. We must carefully consider theadvantages and disadvantages of using each energy source before deciding which energy source(s) it would bebest to use in any particular situation. Electricity is distributed via the National Grid.

Candidates should use their skills, knowledgeand understanding to:■ evaluate different methods of generating electricity

■ evaluate ways of matching supply with demand,either by increasing supply or decreasing demand

■ compare the advantages and disadvantages ofoverhead power lines and underground cables.

P1.4.1 Generating electricity

a) In some power stations an energy source is usedto heat water. The steam produced drives a turbinethat is coupled to an electrical generator.

Energy sources include:

■ the fossil fuels (coal, oil and gas) which areburned to heat water or air

■ uranium and plutonium, when energy fromnuclear fission is used to heat water

■ biofuels that can be burned to heat water.


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Candidates should understand that while small-scaleproduction can be locally useful it is sometimesuneconomic to connect such generation to theNational Grid.

Candidates should understand that carbon capture andstorage is a rapidly evolving technology. To preventcarbon dioxide building up in the atmosphere we cancatch and store it. Some of the best natural containersare old oil and gas fields, such as those under theNorth Sea.


Candidates should be able to identify and label theessential parts of the National Grid.

Candidates should know why transformers are anessential part of the National Grid.

Details of the structure of a transformer and how atransformer works are not required.


Energy sources used in this way include, but are notlimited to, wind, waves, tides and the falling of water inhydroelectric schemes.

Candidates should know that solar cells can be used togenerate electricity and should be able to describe theadvantages and disadvantages of their use.

b) Water and wind can be used to drive turbines directly.

c) Electricity can be produced directly from theSun’s radiation.

d) In some volcanic areas hot water and steam rise tothe surface. The steam can be tapped and used todrive turbines. This is known as geothermal energy.

e) Small-scale production of electricity may be useful insome areas and for some uses, eg hydroelectricityin remote areas and solar cells for roadside signs.

f) Using different energy resources has different effectson the environment. These effects include:

■ the release of substances into the atmosphere

■ the production of waste materials

■ noise and visual pollution

■ the destruction of wildlife habitats.

P1.4.2 The National Grid

a) Electricity is distributed from power stations toconsumers along the National Grid.

b) For a given power, increasing the voltage reducesthe current required and this reduces the energylosses in the cables.

c) The uses of step-up and step-down transformers inthe National Grid.


■ investigating the effect of changing different variables on the output of solar cells, eg distance from the lightsource, the use of different coloured filters and the area of the solar cells

■ planning and carrying out an investigation into the effect of changing different variables on the output of modelwind turbines, eg the number or pitch of the blades, the wind velocity

■ demonstrating a model water turbine linked to a generator

■ modelling the National Grid.


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Candidates should understand that in a transversewave the oscillations are perpendicular to the directionof energy transfer. In a longitudinal wave the oscillationsare parallel to the direction of energy transfer.


Candidates should know the order of electromagneticwaves within the spectrum, in terms of energy,frequency and wavelength.

Candidates should appreciate that the wavelengths varyfrom about 10–15 metres to more than 104 metres.


Knowledge and understanding of waves used forcommunication is limited to sound, light, microwaves,radio waves and infrared waves.

P1.5 The use of waves for communication and to provide evidence that the universe isexpanding

Electromagnetic radiations travel as waves and move energy from one place to another. They can all travel througha vacuum and do so at the same speed. The waves cover a continuous range of wavelengths called theelectromagnetic spectrum.

Sound waves and some mechanical waves are longitudinal, and cannot travel through a vacuum.

Current evidence suggests that the universe is expanding and that matter and space expanded violently andrapidly from a very small initial ‘point’, ie the universe began with a ‘big bang’.

Candidates should use their skills, knowledgeand understanding to:■ compare the use of different types of waves for

communication

■ evaluate the possible risks involving the use ofmobile phones

■ consider the limitations of the model that scientistsuse to explain how the universe began and why theuniverse continues to expand.

P1.5.1 General properties of waves

a) Waves transfer energy.

b) Waves may be either transverse or longitudinal.

c) Electromagnetic waves are transverse, sound wavesare longitudinal and mechanical waves may be eithertransverse or longitudinal.

d) All types of electromagnetic waves travel at the samespeed through a vacuum (space).

e) Electromagnetic waves form a continuous spectrum.


v is speed in metres per second, m/s

f is frequency in hertz, Hz

� is wavelength in metres, m

Candidates are not required to recall the value of thespeed of electromagnetic waves through a vacuum.

Candidates will be expected to be familiar withsituations in which such waves are typically used andany associated hazards, eg:

■ radio waves – television, and radio (includingdiffraction effects)

■ microwaves – mobile phones and satellitetelevision

■ infra red – remote controls

■ visible light – photography.


Candidates should appreciate that significant diffractiononly occurs when the wavelength of the wave is of thesame order of magnitude as the size of the gap orobstacle.

Waves are not refracted if travelling along the normal.

Snell’s law and the reason why waves are refracted arenot required.


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Candidates will be expected to be able to construct raydiagrams.

f) Longitudinal waves show areas of compression andrarefaction.

g) Waves can be reflected, refracted and diffracted.

h) Waves undergo a change of direction when theyare refracted at an interface.

i) The terms frequency, wavelength and amplitude.

j) All waves obey the wave equation:

v = f � �

k) Radio waves, microwaves, infra red and visible lightcan be used for communication.

P1.5.2 Reflection

a) The normal is a construction line perpendicular to thereflecting surface at the point of incidence.

b) The angle of incidence is equal to the angle ofreflection.

c) The image produced in a plane mirror is virtual,upright and latterally inverted.


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Sound is limited to human hearing and no details of thestructure of the ear are required.


The following should be included:

■ the wave source could be light, sound ormicrowaves

■ when the source moves away from the observer,the observed wavelength increases and thefrequency decreases

■ when the source moves towards the observer, theobserved wavelength decreases and the frequencyincreases.

P1.5.3 Sound

a) Sound waves are longitudinal waves and causevibrations in a medium, which are detected as sound.

b) The pitch of a sound is determined by its frequencyand loudness by its amplitude.

c) Echoes are reflections of sounds.

P1.5.4 Red-shift

a) If a wave source is moving relative to an observerthere will be a change in the observed wavelengthand frequency. This is known as the Doppler effect.

b) There is an observed increase in the wavelength oflight from most distant galaxies. The further awaythe galaxies are, the faster they are moving, and thebigger the observed increase in wavelength. Thiseffect is called red-shift.

c) How the observed red-shift provides evidence thatthe universe is expanding and supports the‘Big Bang’ theory (that the universe began froma very small initial point).

d) Cosmic microwave background radiation (CMBR)is a form of electromagnetic radiation filling theuniverse. It comes from radiation that was presentshortly after the beginning of the universe.

e) The ‘Big Bang’ theory is currently the only theorythat can explain the existence of CMBR.


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■ reflecting light off a plane mirror at different angles

■ using a class set of skipping ropes to investigate frequency and wavelength

■ demonstrating transverse and longitudinal waves with a slinky spring

■ carrying out refraction investigations using a glass block

■ carrying out investigations using ripple tanks, including the relationship between depth of water and speed of wave

■ investigating the range of Bluetooth or infrared communications between mobile phones and laptops

■ demonstrating the Doppler effect for sound.


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3.6 Unit 4: Controlled Assessment

3.6.1 Introduction

This unit is assessed by Controlled Assessment. It isworth 25% of the total marks and consists of aminimum of one practical investigation based ontopics in the specification.

Access arrangements (see sections 4.5 and 5.4) canenable candidates with special needs to undertake thisassessment.

Teachers are encouraged to undertake a wide range ofpractical and investigative work, including fieldwork,with their candidates. We take the view that it is notgood practice to do practical work only for theControlled Assessment. As teachers know well,candidates enjoy and are motivated by practical work.Throughout this specification we have given manyexamples of practical work supporting the sciencecontent. Full details of this practical work are includedin our resources package.

In this unit, candidates use a range of practical skillsand knowledge in one investigation chosen from thosesupplied by AQA. The investigations are based ontopics in the specification. Guidance for teachers willbe given with each investigation. Every year, threeControlled Assessments will be available; one for eachunit. Each task assesses How Science Works skills,not candidates' knowledge and understanding of thescience context.

The right-hand column of the tables below shows theAssessment Focus thread from National StrategiesAPP (Assessing Pupils' Progress). This will enableteachers to ensure progression from KS3 to KS4.

Additional guidance: AF/thread

Candidates should be able to state the purpose 4/2of an investigation in terms of the possiblerelationship between two variables. These willusually be the independent and the dependentvariables. Often there may be a quantitativerelationship between these variables.

The variables may be identified as continuous or 4/2categoric.

Candidates should be able to identify variables 4/2that have been controlled, those that have notbeen controlled and those that cannot becontrolled but should be monitored.

Candidates should be able to identify a control 4/2group that is being used, explain the benefit ofusing a control group and suggest how acontrol group could be set up. Examples mayinclude the use of placebos in testing new drugs.

Candidates should be able to identify the interval 4/3between readings and suggest, with reason,a suitable interval for the independent variable.


Candidates should understand the difference 1/3between a hypothesis and a fact.

Candidates should be able to plan a fair test 1/4to investigate a hypothesis.

A fair test will normally involve changing one 4/2variable (the independent variable) to see whateffect this has on another variable (the dependentvariable) while keeping all other variables (controlvariables) constant.


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SA4.1 Planning an investigation

Candidates should be able to:

SA4.1.1 plan practical ways to answer scientificquestions, by:a) stating the purpose of an investigation

b) recognise significant variables in an investigation

c) recognising a control variable in an investigation

d) understanding the purpose of a control group

e) identifying intervals in measurements.

Candidates should understand:

SA4.1.2 test scientific ideas by:

a) understanding the meaning of the term hypothesis

b) being able to test a hypothesis

c) planning a fair test.


Candidates should appreciate when a trial run 5/1would be appropriate and be able to suggestthe values of the variables to be used in atrial run.

Sample size is important and candidates should 4/3be able to suggest why a particular sample sizeis the most appropriate.

Candidates should appreciate that technology 4/1such as data logging may provide a better meansof obtaining data. They should be able tosuggest appropriate technology for collectingdata and explain why a particular technologyis the most appropriate. Candidates shoulduse ICT whenever appropriate.


Candidates will be expected to independently 4/4recognise a range of familiar hazards and consult appropriate resources and expert advice.

Candidates should assess risks to themselves 4/4and others and take action to reduce these risksby adapting their approaches to practical workin order to control risk.


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AF/thread

4/3

SA4.1.3 devise appropriate methods for thecollection of numerical and other data, by:a) carrying out preliminary work

b) understanding sample size

c) using appropriate technology.

SA4.2 Assess and manage risks when carrying out practical work


SA4.2.1 assess and manage risks when carryingout practical work, by:a) identifying some possible hazards in practical

situations

b) suggesting ways of managing risks.

SA4.3 Collect primary and secondary data


SA4.3.1 make observations, by:a) making simple observations from first hand evidence

of an object or an event

b) carrying out practical work and research.


4/1

4/1

Candidates should appreciate why a measuring 4/1instrument needs to be calibrated accuratelyand be able to describe how an instrumentcould be calibrated.

Candidates should be able to choose the correct 4/1scale to use for the intended measurement, andrecognise whether the chosen instrument hasthe required resolution.


Candidates should be able to explain whether 4/3results can be considered valid and recognisewhen an instrument or technique might not bemeasuring the variable intended.

Candidates should recognise that a second 4/3set of readings with another instrument or bya different observer could be used to crosscheck results.

Candidates should understand that accuracy 4/3is a measure of how close the measuredvalue is to the true value.

Candidates should understand that resolution 4/3is the smallest change in the quantity beingmeasured (input) of a measuring instrumentthat gives a perceptible change in theindication (output).

Candidates should be able to distinguish between 4/3accuracy and precision when applied to aninstrument's readings.

Candidates should be able to identify the upper 4/3and lower limits of the range and which extraresults, within or outside the range, would beappropriate.


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SA4.3.2 demonstrate the correct use ofequipment, by:a) choosing the most appropriate equipment or

technique for the task

b) understanding why a particular technique orpiece of equipment is the most suitable for the task

c) knowing that a measuring instrument needs to becalibrated before use

d) understanding the meaning of the term resolutionwhen applied to a measuring instrument.


SA4.3.3 demonstrate an understanding of the needto acquire high-quality data, by:a) appreciating that, unless certain variables are

controlled, the results may not be valid

b) identifying when repeats are needed in order toimprove reliability

c) recognising the value of repeated readings toestablish accuracy

d) considering the resolution of the measuring device

e) considering the precision of the measured datawhere precision is indicated by the degree of scatterfrom the mean.

f) identifying the range of the measured data.


5/1

Candidates should be able to calculate the 5/1mean of a set of at least three results, recognisingthe need to exclude anomalies before calculatingmeans to an appropriate number of decimalplaces.


Candidates should be able to draw up a table 3/2of two or more columns, with correct headingsand units, adequately representing the dataobtained.

Candidates should be able to construct an 3/2appropriate graphical representation of the datasuch as a bar chart or line graph and draw a lineof best fit when appropriate. Candidates mayuse ICT to produce their graphs or charts.

Candidates should be able to identify the most 3/1appropriate method of display for any given setof data.


Candidates should recognise that opinion may 2/1be influenced by economic, ethical, moral, socialor cultural considerations.

1/2


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SA4.4 Select and process primary and secondary data


SA4.4.1 show an understanding of the value ofmeans, by:a) appreciating when it is appropriate to

calculate a mean

b) calculating the mean of a set of at leastthree results.


SA4.4.2 demonstrate an understanding of how datamay be displayed, by:

a) drawing tables

b) drawing charts and graphs

c) choosing the most appropriate form of presentation.

SA4.5 Analyse and interpret primary and secondary data


SA4.5.1 distinguish between a fact and anopinion, by:a) recognising that an opinion might be influenced

by factors other than scientific fact

b) identifying scientific evidence that supportsan opinion.


Candidates should be able to identify from data 5/2whether there is any variation other than obviousanomalies, and identify a potential cause forvariation or uncertainty.

Candidates should appreciate that if a data set 5/2contains random errors, repeating the readings andcalculating a new mean can reduce their effect.

Candidates should appreciate that human errormight be the cause of inaccurate measurementsand explain how human error might have influencedthe accuracy of a measurement or might haveintroduced bias into a set of readings.

Candidates should be able to identify anomalous 5/2results and suggest what should be done about them.

Candidates should be able to identify when a data 5/2set contains a systematic error and appreciate thatrepeat readings cannot reduce the effect ofsystematic errors.

Candidates should realise that a zero error is a type ofsystematic error. Candidates should be able to identifywhether a scale has been incorrectly used and suggesthow to compensate for a zero error.


Candidates should be able to use terms such as 5/3linear or directly proportional, or describe acomplex relationship.


Candidates should be able to state simply what 5/3the evidence shows to justify a conclusion, andrecognise the limitations of the evidence.

Candidates should appreciate that secondary 5/3sources or alternative methods can increasereliability and validity.

Candidates should be able to suggest that extra 5/4evidence might be required for a conclusion to bemade, and be able to describe the extra evidencerequired.

Candidates should appreciate that the evidence 5/4obtained may not allow the conclusion to be madewith confidence. Candidates should be able to explainwhy the evidence obtained does not allow theconclusion to be made with confidence.


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SA4.5.2 review methodology to assessfitness for purpose, by:a) identifying causes of variation in data

b) recognising and identifying the cause of randomerrors

c) recognising and identifying the cause of anomalousresults

d) recognising and identifying the cause of systematicerrors.


SA4.5.3 identify patterns in data, by:a) describing the relationship between two variables.

SA4.5.4 draw conclusions using scientific ideasand evidence, by:a) writing a conclusion, based on evidence that relates

correctly to known facts

b) using secondary sources

c) identifying extra evidence that is required for aconclusion to be made

d) evaluating methods of data collection.


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Guidance on Managing Controlled Assessment

What is Controlled Assessment?

For each subject, Controlled Assessment regulations from Ofqual stipulate the level of control required for tasksetting, task taking and task marking. The ‘task’ is what the candidate has to do; the ‘level of control’ indicates thedegree of freedom given to teachers and candidates for different aspects of the ‘task’.

For GCSE Science A, the regulations state: For this specification, this means:

Task setting – high control ■ We prepare equivalent Investigative SkillsAssignments (ISAs) each year.

Task taking ■ We require the practical work and data collection(research/data collection) – limited control to be carried out under teacher supervision,

during normal class contact time.

■ If more than one lesson is used, candidates’ dataand research work must be collected at the endof each lesson.

■ Candidates can work together during theinvestigation, but each candidate must contributeto the collection of the data and process the dataindividually.

■ Results should be pooled for research.

Task taking ■ ISA tests should be taken under formal (analysis and evaluation of findings) – high control supervision, in silence, without cooperation

between candidates.

■ Candidates should be given their processed datafor reference during the ISA test, and will also beprovided with a data sheet of secondary data.

■ Teachers should not help candidates answer thequestions.

■ Each ISA has a fixed time limit unless thecandidate is entitled to access arrangements.

■ Candidates’ processed data and their ISA testsare collected by the teacher at the end of eachtest.

Task marking ■ We provide ‘marking guidelines’ for each ISA test. – medium control

■ We moderate your marking.


Candidates will be expected to plan their investigationindependently and should each draw up anappropriate table for recording their results.

While carrying out the investigation, candidates shouldmake and record observations. They should makemeasurements with precision and accuracy. Theyshould record data as it is obtained in a table. Theyshould use ICT where appropriate. Candidates are alsorequired to process the data into a graph or chart.

Candidates’ tables of data and graphs or charts mustbe collected by the teacher at the end of each lesson.Candidates must not be allowed to work on thepresentation or processing of their data betweenlessons, because marks are available for these skills.

The paper containing Section 2 of the ISA should betaken as soon as possible after completion of theinvestigation.

During the test, candidates should work on their ownand in silence. When candidates have completed thetest the scripts must be collected. Teachers arerequired to mark the tests, using the markingguidelines provided by AQA. Tests should be markedin red ink with subtotals placed in the margin.

Teachers are expected to use their professionaljudgement in applying the marking guidelines: forexample, applying it sensibly where candidates havegiven unexpected answers. When teachers havemarked the scripts, they may tell candidates theirmarks but they must not return the scripts. CompletedISAs must be kept under secure conditions while theISA is valid.

Other guidance

Teachers’ Notes will be put on to the AQA websiteprior to the ISAs becoming valid. ISA tests and markingguidelines will be published in advance.

If ISAs are to be used with different classes, centresmust ensure security between sessions.

ISAs have specific submission dates within a one yearperiod. There are two moderation windows – June andJanuary. They may not be submitted in more than oneyear.

Candidates may attempt any number of the ISAssupplied by AQA for a particular subject. The bestmark they achieve from a complete ISA is submitted.

A candidate is only allowed to have one attempt ateach ISA, and this may only be submitted formoderation on one occasion. It would constitutemalpractice if the candidate is found to havesubmitted the same ISA more than once and theycould be excluded from at least this qualification.

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What is the Controlled Assessment like?

The Controlled Assessment comprises an ISA testwhich is assessed in two sections.

Prior to taking Section 1 of the ISA test, candidatesindependently consider the hypothesis they have beengiven and research possible methods for carrying outan experiment to test it. During this research,candidates need to do a risk assessment and alsoresearch the context of the investigation for use inSection 2 of the ISA. Candidates are allowed to makebrief notes on one side of A4 which they can use duringtheir answering of Sections 1 and 2 of the ISA paper.

Section 1 of the ISA test (45 minutes, 20 marks)consists of questions relating to the candidate’s ownresearch.

Following Section 1 candidates carry out their ownexperiment and record and analyse their results.If the candidate’s plan is unworkable, unsafe orunmanageable in the laboratory then they may beprovided with a method – an example of which willbe provided by AQA. For plans that are otherwisegood, but unworkable for a good reason (ie logistical)candidates should not lose any marks. However,where the plan is dangerous or unworkable (from ascientific perspective) this will be reflected in themarking.

Section 2 of the ISA test (50 minutes, 30 marks)consists of questions related to the experimentcandidates have carried out.

They are also provided with a data sheet ofsecondary data by AQA, from which they selectappropriate data to analyse and compare with thehypothesis.

Candidates will be asked to suggest how ideasfrom their investigation and research could be usedwithin a new context.

Using ISAs

The documents provided by AQA for each ISA are:

■ a set of Teachers’ Notes

■ the ISA – Section 1 and Section 2 which are to becopied for each candidate

■ the marking guidelines for the teacher to use.

The Teachers’ Notes provide suggestions on how toincorporate ISAs into the scheme of work. About fivelessons should be allowed for the ISA: one lesson fordiscussion, research and planning; one lesson for thecompletion of Section 1; one or two lessons forcompleting the experiment and processing their resultsand one lesson for completing Section 2 of the ISA.


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3.7 Unit 5: Science A1

Science 1 is half of Biology 1, half of Chemistry 1 andhalf of Physics 1, as follows:

■ Biology 1 sections B1.1 to B1.3

■ Chemistry 1 sections C1.1 to C1.4

■ Physics 1 sections P1.1 to P1.3

See sections 3.3, 3.4 and 3.5 for required content.

3.8 Unit 6: Science A2

Science 2 is half of Biology 1, half of Chemistry 1 andhalf of Physics 1, as follows:

■ Biology 1 sections B1.4 to B1.8

■ Chemistry 1 sections C1.5 to C1.7

■ Physics 1 sections P1.4 to P1.5

See sections 3.3, 3.4 and 3.5 for required content.

Specimen ISAs or ISAs that are no longer valid may begiven to candidates so that they can practise the skillsrequired. In these cases, candidates can be given backtheir completed and marked scripts. However, ISAsthat are currently valid must not be given back tocandidates.

3.9 Mathematical and other requirements


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Mathematical requirements

One learning outcome of this specification is to providelearners with the opportunity to develop their skills incommunication, mathematics and the use oftechnology in scientific contexts. In order to deliver themathematical element of this outcome, assessmentmaterials for this specification contain opportunities forcandidates to demonstrate scientific knowledge usingappropriate mathematical skills.

The areas of mathematics that arise naturally from thescience content in science GCSEs are listed below.This is not a checklist for each question paper orControlled Assessment, but assessments reflect thesemathematical requirements, covering the full range ofmathematical skills over a reasonable period of time.

Candidates are permitted to use calculators in allassessments.

Candidates are expected to use units appropriately.However, not all questions reward the appropriate useof units.

All candidates should be able to:

1 Understand number size and scale and thequantitative relationship between units.

2 Understand when and how to use estimation.

3 Carry out calculations involving +, – , x, ÷, eithersingly or in combination, decimals, fractions,percentages and positive whole number powers.

4 Provide answers to calculations to an appropriatenumber of significant figures.

5 Understand and use the symbols =, <, >, ~.

6 Understand and use direct proportion and simpleratios.

7 Calculate arithmetic means.

8 Understand and use common measures andsimple compound measures such as speed.

9 Plot and draw graphs (line graphs, bar charts, piecharts, scatter graphs, histograms) selectingappropriate scales for the axes.

10 Substitute numerical values into simple formulaeand equations using appropriate units.

11 Translate information between graphical andnumeric form.

12 Extract and interpret information from charts,graphs and tables.

13 Understand the idea of probability.

14 Calculate area, perimeters and volumes of simpleshapes.

In addition, Higher Tier candidates should be able to:

15 Interpret, order and calculate with numbers writtenin standard form.

16 Carry out calculations involving negative powers(only -1 for rate).

17 Change the subject of an equation.

18 Understand and use inverse proportion.

19 Understand and use percentiles and deciles.

Units, symbols and nomenclature

Units, symbols and nomenclature used in examinationpapers will normally conform to the recommendationscontained in the following:

■ The Language of Measurement: Terminology usedin school science investigations. Association forScience Education (ASE), 2010.ISBN 978 0 86357 424 5.

■ Signs, Symbols and Systematics: The ASEcompanion to 16–19 Science. Association forScience Education (ASE), 2000.ISBN 978 0 86357 312 5.

■ Signs, Symbols and Systematics – the ASEcompanion to 5–16 Science. Association forScience Education (ASE), 1995.ISBN 0 86357 232 4.

Equation sheet

An equation sheet will be provided for the physics unitand for the combined papers in Units 5 and 6.

Candidates will be expected to select the appropriateequation to answer the question.

Data sheet

A data sheet will be provided for the chemistry unit andfor the combined papers in Units 5 and 6. Thisincludes a periodic table and other information.Candidates will be expected to select the appropriateinformation to answer the question.


Scheme of Assessment4.1 Aims and learning outcomes

GCSE specifications in science should encouragelearners to be inspired, motivated and challenged byfollowing a broad, coherent, practical, satisfying andworthwhile course of study. They should provide insightinto and experience of how science works, stimulatinglearners’ curiosity and encouraging them to engagewith science in their everyday lives and to makeinformed choices about further study and about careerchoices.

GCSE specifications in science must enable learners to:

■ develop their knowledge and understanding of thematerial, physical and living worlds

■ develop their understanding of the nature ofscience and its applications and the inter-relationships between science and society

■ develop an understanding of the importance ofscale in science

■ develop and apply their knowledge andunderstanding of the scientific process throughhypotheses, theories and concepts

■ develop their understanding of the relationshipsbetween hypotheses, evidence, theories andexplanations

■ develop their awareness of risk and the ability toassess potential risk in the context of potentialbenefits

■ develop and apply their observational, practical,enquiry and problem-solving skills andunderstanding in laboratory, field and other learningenvironments

■ develop their ability to evaluate claims based onscience through critical analysis of themethodology, evidence and conclusions

■ develop their skills in communication, mathematicsand the use of technology in scientific contexts.

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Weighting of Assessment Objectives for GCSE Science A

The table below shows the approximate weighting of each of the Assessment Objectives in the GCSE units.

Route 1 (4405)

Assessment Objectives Unit Weightings (%) Overall weighting of AOs (%)

UNIT1 2 3 4

AO1 12.5 12.5 12.5 0 37.5

AO2 7.5 7.5 7.5 12.5 35.0

AO3 5.0 5.0 5.0 12.5 27.5

Overall weighting of units (%) 25 25 25 25 100

Route 2 (4406)

Assessment Objectives Unit Weightings (%) Overall weighting of AOs (%)

UNIT5 6 4

AO1 17.5 20 0 37.5

AO2 10.5 12.0 12.5 35.0

AO3 7.0 8.0 12.5 27.5

Overall weighting of units (%) 35 40 25 100


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Quality of Written Communication

In GCSE specifications that require candidates toproduce written material in English, candidates mustdo the following:

■ ensure that text is legible and that spelling,punctuation and grammar are accurate so thatmeaning is clear

■ select and use a form and style of writingappropriate to purpose and to complex subjectmatter

■ organise information clearly and coherently, usingspecialist vocabulary when appropriate.

In this specification, Quality of Written Communication(QWC) is assessed in Units 1, 2, 3 and 4 by means oflonger response questions. These questions are clearlyindicated in each question paper. In these questions,candidates cannot obtain full marks unless theyaddress the three bullet points above.

4.2 Assessment Objectives

The assessment units assess the following AssessmentObjectives (AOs) in the context of the content and skillsset out in Section 3 (Subject Content).

AO1 Recall, select and communicate theirknowledge and understanding of science

AO2 Apply skills, knowledge and understanding ofscience in practical and other contexts

AO3 Analyse and evaluate evidence, make reasonedjudgements and draw conclusions based onevidence


4.4 Previous Learning requirements

There are no previous learning requirements. However,any requirements set for entry to a course based onthis specification are at your centre’s discretion.

4.5 Access to assessment: diversity and inclusion

GCSEs often need to assess a wide range ofcompetences. This is because they are generalqualifications designed to prepare candidates for awide range of occupations and further study.

The revised GCSE Qualification and subject criteriawere reviewed to see whether any of the skills orknowledge needed by the subject presented apossible difficulty to any candidates, whatever theirethnic background, religion, sex, age, disability orsexuality. If there were difficulties, the situation wasreviewed again to make sure that such tests of specificcompetences were only included if they were importantto the subject. The findings were discussed withgroups who represented the interests of a diverserange of candidates.

Arrangements are made for candidates with specialneeds to help them access the assessments as longas the competences being tested are not changed.Because of this, most candidates will be able toaccess any part of the assessment. Section 5.4provides further details.

4.3 National criteria

This specification complies with:

■ the Subject Criteria for GCSE Science, includingthe rules for Controlled Assessment

■ the Code of Practice

■ the GCSE Qualification Criteria

■ the Arrangements for the Statutory Regulation ofExternal Qualifications in England, Wales andNorthern Ireland: Common Criteria

■ the requirements for qualifications to provideaccess to Levels 1 and 2 of the NationalQualification Framework.

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5.2 Entries

Please check the current version of Entry Proceduresand Codes for up-to-date entry procedures. Youshould use the following entry codes for the units andfor certification.

Unit 1 – BL1FP or BL1HP

Unit 2 – CH1FP or CH1HP

Unit 3 – PH1FP or PH1HP

Unit 4 – SCA4P

Unit 5 – SCA1FP or SCA1HP

Unit 6 – SCA2FP or SCA2HP

GCSE certification – 4405 (Route 1) 4406 (Route 2)

The 40% terminal rule for GCSE means that 40% ofthe assessment must be taken in the examinationseries in which the qualification is awarded. Therefore,in this specification:

■ candidates following Route 1 must take aminimum of two units in the series in which thequalification is awarded

■ candidates following Route 2 must take aminimum of either Unit 6 or Units 5 and 4 in theseries in which the qualification is awarded.

The results from 40% terminal assessment mustcontribute to the candidate’s final grade, even if acandidate has a better result from a previous series.

Please note that entries are not allowed in the sameexamination series for the following combination ofGCSE certifications:

■ GCSE Science A (Route 1) and GCSE Biology

■ GCSE Science A (Route 1) and GCSE Chemistry

■ GCSE Science A (Route 1) and GCSE Physics.

Administration5.1 Availability of assessment units and certificationExaminations and certification for this specification are available as follows.

Two routes to GCSE Science A are available:

■ Route 1 Units 1, 2, 3 and 4

■ Route 2 Units 5, 6 and 4.

Route 1 (4405) Availability of units Availability of certification

UNIT1 2 3 4 GCSE

Biology 1 Chemistry 1 Physics 1January 2012 ✓ ✓ ✓

June 2012 ✓ ✓ ✓ ✓ ✓

January 2013 and after ✓ ✓ ✓ ✓ ✓

June 2013 and after ✓ ✓ ✓ ✓ ✓

Route 2 (4406) Availability of units Availability of certification

UNIT5 6 4 GCSE

January 2012 ✓ ✓

June 2012 ✓ ✓ ✓ ✓

January 2013 and after ✓ ✓ ✓ ✓

June 2013 and after ✓ ✓ ✓ ✓Ad

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5.4 Access arrangements, reasonable adjustments andspecial consideration

We have taken note of the equality and discriminationlegislation and the interests of minority groups indeveloping and administering this specification.

We follow the guidelines in the Joint Council forQualifications (JCQ) document: Access Arrangements,Reasonable Adjustments and Special Consideration:General and Vocational Qualifications. This is publishedon the JCQ website (www.jcq.org.uk) or you canfollow the link from our website aqa.org.uk

Access arrangements

We can arrange for candidates with special needs toaccess an assessment. These arrangements must bemade before the examination. For example, we canproduce a Braille paper for a candidate with sightproblems.

Reasonable adjustments

An access arrangement which meets the needs of aparticular disabled candidate would be a reasonableadjustment for that candidate. For example, a Braillepaper would be a reasonable adjustment for a Braillereader but not for a candidate who did not read Braille.The Disability Discrimination Act requires us to makereasonable adjustments to remove or lessen anydisadvantage affecting a disabled candidate.

Special consideration

We can give special consideration to candidateswho have had a temporary illness, injury or seriousproblem such as the death of a relative, at the time ofthe examination. We can only do this after theexamination.

The Examinations Officer at the centre should applyonline for access arrangements and specialconsideration by following the e-AQA link from ourwebsite aqa.org.uk

5.5 Examination language

We will only provide units for this specification inEnglish.

5.6 Qualification titles

Qualifications based on this specification are:

■ AQA GCSE in Science A.

5.3 Private candidates

This specification is available to private candidatesunder certain conditions. Because of the ControlledAssessment, candidates must attend an AQA centre,which will supervise and mark the Controlled

Assessment. Private candidates should write to us fora copy of Supplementary Guidance for PrivateCandidates (for Controlled Assessment specificationwith practical activities).

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5.7 Awarding grades and reporting results

This GCSE will be graded on an eight-grade scale: A*, A, B, C, D, E, F and G. Candidates who fail to reach theminimum standard for grade G will be recorded as ‘U’ (unclassified) and will not receive a qualification certificate.

We will publish the minimum raw mark for each grade and for each unit when we issue candidates’ results. We willreport a candidate’s unit results to your centre in terms of uniform marks and qualification results in terms ofuniform marks and grades.

For each unit, the uniform mark corresponds to a grade as follows.

Unit 1: Biology 1(maximum uniform mark = 100)

Grade Uniform Mark Range

A* 90–100

A 80–89

B 70–79

C 60–69

D 50–59

E 40– 49

F 30–39

G 20–29

U 0–19

Unit 3: Physics 1(maximum uniform mark = 100)


A* 90–100

A 80–89

B 70–79

C 60–69

D 50–59

E 40– 49

F 30–39

G 20–29

U 0–19

Unit 2: Chemistry 1(maximum uniform mark = 100)


A* 90–100

A 80–89

B 70–79

C 60–69

D 50–59

E 40– 49

F 30–39

G 20–29

U 0–19

Unit 4: Controlled Assessment(maximum uniform mark = 100)


A* 90–100

A 80–89

B 70–79

C 60–69

D 50–59

E 40– 49

F 30–39

G 20–29

U 0–19


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We calculate a candidate’s total uniform mark by adding together the uniform marks for the units. We convert thistotal uniform mark to a grade as follows.

GCSE Science A(maximum uniform mark = 400)


A* 360–400

A 320–359

B 280–319

C 240–279

D 200–239

E 160–199

F 120–159

G 80–119

U 0–79

Unit 5: Science A 1(maximum uniform mark = 140)


A* 126–140

A 112–125

B 98–111

C 84–97

D 70–83

E 56–69

F 42–55

G 28–41

U 0–27

Unit 6: Science A 2(maximum uniform mark = 160)


A* 144–160

A 128–143

B 112–127

C 96–111

D 80–95

E 64–79

F 48–63

G 32–47

U 0–31

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5.8 Grading and tiers

The Controlled Assessment is not tiered and the fullrange of grades A*–G is available to candidates for thisunit.

For the other units, candidates take either theFoundation Tier or the Higher Tier. For candidatesentered for the Foundation Tier, grades C–G areavailable; for candidates entered for the Higher Tier,A*–D are available. There is a safety net for candidatesentered for the Higher Tier, where an allowed Grade Ewill be awarded if candidates just fail to achieve gradeD. Candidates who fail to achieve a grade E on theHigher Tier or grade G on the Foundation Tier will bereported as unclassified.

For the tiered units, candidates cannot obtain aUniform Mark Scale (UMS) score corresponding to agrade that is above the range for the tier entered. Themaximum UMS score for candidates on the

Foundation Tier written paper for units 1, 2 and 3 is 69.For Unit 5, the maximum UMS on the Foundation Tierpaper is 97 and for Unit 6 it is 111. In other words, theycannot achieve a UMS score corresponding to a gradeB. Candidates who just fail to achieve grade E on theHigher Tier paper receive the UMS scorecorresponding to their raw mark, ie they do not receivea UMS score of zero.

During the awarding procedures the relationshipbetween raw marks and UMS score is decided foreach tier separately. Where a grade is available on twotiers, for example grade C, the two raw marks chosenas the boundary for the grade on the two tiers aregiven the same UMS score. Therefore, candidatesreceive the same UMS score for the sameachievement whether this is demonstrated on theFoundation or the Higher Tier assessments.

5.9 Re-sits and shelf life of unit results

Unit results remain available to count towardscertification within the shelf life of the specification,whether or not they have already been used.

Candidates may re-sit a unit once only.

The better result for each unit will count towards thefinal qualification provided that the 40% rule issatisfied.

Candidates may re-sit the qualification an unlimitednumber of times.

Candidates will be graded on the basis of the worksubmitted for assessment.

Candidates must take units comprising at least 40% ofthe total assessment in the series in which they enterfor certification.

Candidates’ grades are based on the work they submitfor assessment.


Controlled Assessment administrationThe Head of Centre is responsible for making sure that Controlled Assessment work is conducted in line with ourinstructions and JCQ instructions.

6.1 Authentication of Controlled Assessment work

To meet the requirements of the Code of Practice, weneed the following.

■ Candidates must sign the Candidate RecordForm to confirm that the work they have handedin is their own.

■ Teachers and assessors must confirm on theCandidate Record Form that the work marked isonly that done by that candidate and wasconducted in line with the conditions in thespecification document (authenticationdeclaration).

■ Centres must give a mark of zero if candidatescannot confirm the work handed in forassessment is their own.

You should attach the completed Candidate RecordForm for each candidate to his or her work. Allteachers who have marked the work of any candidateentered for each component must sign the declarationthat the work is genuine.

If you have doubts about signing the authenticationdeclaration, you should follow these guidance points.

■ If you believe that a candidate had additionalassistance and that this is acceptable within theguidelines for the relevant specification, youshould award a mark which covers only thecandidate’s achievement without any help. (Youshould sign the authentication declaration andgive information on the relevant form.)

■ If you cannot sign the authentication declaration,the candidate’s work cannot be accepted forassessment.

If, during the external moderation process, there is noevidence that the work has been authenticated, we willaward a mark of zero.

6.2 Malpractice

You should let candidates know about our malpracticeregulations.

Candidates must not:

■ submit work that is not their own

■ lend work to other candidates

■ give other candidates access to, or the use of,their own independently sourced research material(this does not mean that candidates cannot lendtheir books to another candidate, but thatcandidates should be stopped from copying othercandidates’ research)

■ include work copied directly from books, theInternet or other sources withoutacknowledgement of the source

■ hand in work typed or word-processed bysomeone else without acknowledgement.

These actions are considered malpractice, for which apenalty (for example being disqualified from the exam)will be applied.

If you suspect malpractice, you should consult yourExaminations Officer about the procedure to befollowed.

Where you suspect malpractice in ControlledAssessments after the candidate has signed thedeclaration of authentication, your Head of Centremust submit full details of the case to us at the earliestopportunity. The form JCQ/M1 should be used.Copies of the form can be found on the JCQ website(www.jcq.org.uk).

Malpractice in Controlled Assessments discoveredprior to the candidate signing the declaration ofauthentication need not be reported to us, but shouldbe dealt with in accordance with your centre’s internalprocedures. We would expect you to treat such casesvery seriously. Details of any work which is not thecandidate’s own must be recorded on the CandidateRecord Form or other appropriate place.

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6.3 Teacher standardisation

We will hold standardising meetings for teachers eachyear, usually in the autumn term, for ControlledAssessment. At these meetings we will providesupport in explaining tasks in context and using themarking criteria.

If your centre is new to this specification, you mustsend a representative to one of the meetings. If youhave told us you are a new centre, either by sending usan Intention to Enter or an Estimate of Entry, or bycontacting the subject team, we will contact you toinvite you to a meeting.

We will also contact centres in the following cases:

■ if the moderation of Controlled Assessment workfrom the previous year has shown a seriousmisinterpretation of the Controlled Assessmentrequirements

■ if a significant adjustment has been made to acentre’s marks.

In these cases, you will be expected to send arepresentative to one of the meetings. If your centredoes not fall into one of these categories you canchoose whether or not to come to a meeting. If youcannot attend and would like a copy of the writtenmaterials used at the meeting, you should contactthe subject administration team [email protected]

6.4 Internal standardisation of marking

Centres must have consistent marking standards for allcandidates. One person must be responsible forensuring that work has been marked to the samestandard, and they need to sign the Centre DeclarationSheet to confirm that internal standardisation has takenplace.

Internal standardisation may involve:

■ all teachers marking some sample pieces of workand identifying differences in marking standards

■ discussing any differences in marking at a trainingmeeting for all teachers involved in theassessment

■ referring to reference and archive material, such asprevious work or examples from our teacherstandardising meetings.

6.5 Annotation of Controlled Assessment work

The Code of Practice states that the awarding bodymust make sure that teachers marking ControlledAssessments clearly show how the marks have beenawarded in line with the guidance provided. For thisspecification, the marking guidelines provided by AQAand teachers must use these guidelines to annotatecandidates’ work.

Annotation helps our moderators to see as precisely aspossible where the teacher has identified thatcandidates have met the requirements of the markingguidelines.

Annotation includes:

■ ticks and numbers showing how many markshave been awarded

■ comments on the work that refer to the markingguidelines.


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6.6 Submitting marks and sample work for moderation

The total mark for each candidate must be sent to usand the moderator on the mark forms provided, orelectronically by Electronic Data Interchange (EDI) bythe date given (see www.aqa.org.uk/deadlines/coursework_deadlines.php). Our moderator will

contact you to let you know which pieces of work mustbe sent to them as part of the sample (please seeSection 7.1 for more guidance on sending in samples).

6.7 Factors affecting individual candidates

You should be able to accept the occasional absenceof candidates by making sure they have the chance tomake up missed Controlled Assessments. (You mayorganise an alternative supervised time session forcandidates who are absent at the time the centreoriginally arranged).

If work is lost, you must tell us immediately the date itwas lost, how it was lost, and who was responsible.Inform our Centre and Candidate Support Servicesusing the JCQ form Notification of Lost CourseworkJCQ/LCW form 15.

Where special help that goes beyond normal learningsupport is given, use the Candidate Record Form toinform us so that this help can be taken into accountduring moderation.

Candidates who move from one centre to anotherduring the course sometimes need additional help tomeet the requirements of a scheme of ControlledAssessment work. How this can be dealt with dependswhen the move takes place. If it happens early in thecourse the new centre should be responsible forControlled Assessment work. If it happens late in thecourse it may be possible to arrange for the moderatorto assess the work as a candidate who was ‘EducatedElsewhere’. Centres should contact us by [email protected] as early as possible foradvice about appropriate arrangements in individualcases.

6.8 Keeping candidates’ work

From the time the work is marked, your centre mustkeep the work of all candidates, with CandidateRecord Forms attached, under secure conditions, toallow the work to be available during the moderation

period or should there be an Enquiry about Results.You may return the work to candidates after thedeadline for Enquiries about Results, or once anyenquiry is resolved.

6.9 Grade boundaries on Controlled Assessment

The grade boundaries for the Controlled Assessmentwill be decided at the grade award meeting for eachexamination series and may, therefore, vary over time.


Moderation7.1 Moderation procedures

Controlled Assessment work is moderated by inspectinga sample of candidates’ work sent (by post orelectronically) from the centre to a moderator appointedby us. The centre marks must be sent to us and themoderator by the deadline given (see www.aqa.org.uk/deadlines/coursework_deadlines.php). Centresentering fewer candidates than the minimum samplesize (and centres submitting work electronically) shouldsend the work of all of their candidates. Centres enteringlarger numbers of candidates will be told whichcandidates’ work must be sent as part of the samplesent in for moderation.

Following the re-marking of the sample work, themoderator’s marks are compared with the centre marks

to check whether any changes are needed to bring thecentre’s assessments in line with our agreed standards.In some cases the moderator may need to ask for thework of other candidates in the centre. To meet thisrequest, centres must keep the Controlled Assessmentwork and Candidate Record Forms of every candidateentered for the examination under secure conditions,and they must be prepared to send it to us or themoderator when it is requested. Any changes to markswill normally keep the centre’s rank order, but wheremajor differences are found, we reserve the right tochange the rank order.

7.2 Consortium arrangements

If you are a consortium of centres with joint teachingarrangements (where candidates from different centreshave been taught together but where they are enteredthrough the centre at which they are on roll), you musttell us by filling in the JCQ/CCA form Application forCentre Consortium Arrangements for Centre-assessedWork.

You must choose a consortium coordinator who canspeak to us on behalf of all centres in the consortium. Ifthere are different coordinators for differentspecifications, a copy of the JCQ/CCA form must besent in for each specification.

We will allocate the same moderator to each centre inthe consortium and the candidates will be treated as asingle group for moderation.

7.3 Procedures after moderation

When the results are published, we will give centresdetails of the final marks for the Controlled Assessmentwork.

We will return candidates’ work to you after the exam.You will receive a report, at the time results are issued,

giving feedback on any adjustments that were made toyour marks.

We may keep some candidates’ work for awarding,archive or standardising purposes and will inform you ifthis is the case.

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AppendicesA Grade descriptions

Grade descriptions are provided to give a generalindication of the standards of achievement likely tohave been shown by candidates awarded particulargrades. The descriptions must be interpreted in relationto the content in the specification; they are notdesigned to define that content.

The grade awarded will depend in practice upon theextent to which the candidate has met the assessmentobjectives overall. Shortcomings in some aspects ofcandidates’ performance in the assessment may bebalanced by better performances in others.

Grade A

Candidates recall, select and communicate preciseknowledge and detailed understanding of science. Theydemonstrate a comprehensive understanding of thenature of science, its laws, its applications, and theinfluences of society on science and science on society.They understand the relationships between scientificadvances, their ethical implications and the benefits andrisks associated with them. They use scientific andtechnical knowledge, terminology and conventionsappropriately and consistently showing a detailedunderstanding of scale in terms of time, size and space.

They apply appropriate skills, including communication,mathematical and technological skills, knowledge andunderstanding effectively in a wide range of practicaland other contexts. They show a comprehensiveunderstanding of the relationships betweenhypotheses, evidence, theories and explanations andmake effective use of models to explain phenomena,events and processes. They use a wide range ofappropriate methods, sources of information and dataconsistently, applying relevant skills to address scientificquestions, solve problems and test hypotheses.

Candidates analyse, interpret and critically evaluate abroad range of quantitative and qualitative data andinformation. They evaluate information systematically todevelop arguments and explanations, taking account ofthe limitations of the available evidence. They makereasoned judgements consistently and draw detailed,evidence-based conclusions.

Grade C

Candidates recall, select and communicate secureknowledge and understanding of science. Theydemonstrate understanding of the nature of science,its laws, its applications and the influence of society onscience and science on society. They understand thatscientific advances may have ethical implications,

benefits and risks. They use scientific and technicalknowledge, terminology and conventions appropriately,showing understanding of scale in terms of time, sizeand space.

They apply appropriate skills, including communication,mathematical and technological skills, knowledge andunderstanding in a range of practical and othercontexts. They recognise, understand and usestraightforward links between hypotheses, evidence,theories and explanations. They use models to explainphenomena, events and processes. They use a rangeof appropriate methods, sources of information anddata, applying their skills to address scientificquestions, solve problems and test hypotheses.

Candidates analyse, interpret and evaluate a range ofquantitative and qualitative data and information. Theyunderstand the limitations of evidence and developarguments with supporting explanations. They drawconclusions consistent with the available evidence.

Grade F

Candidates recall, select and communicate their limitedknowledge and understanding of science. They have alimited understanding that scientific advances mayhave ethical implications, benefits and risks. Theyrecognise simple inter-relationships between scienceand society. They show limited scientific and technicalknowledge, terminology and conventions, showingsome understanding of scale in terms of time, size andspace.

They apply skills, including limited communication,mathematical and technological skills, knowledge andunderstanding in practical and some other contexts.They show limited understanding of the nature ofscience and its applications. They can explainstraightforward models of phenomena, events andprocesses. Using a limited range of skills andtechniques, they answer scientific questions, solvestraightforward problems and test ideas.

Candidates interpret and evaluate limited quantitativeand qualitative data and information from a narrowrange of sources. They can draw elementaryconclusions having collected limited evidence.

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B Spiritual, moral, ethical, social, legislative, sustainabledevelopment, economic and cultural issues, and healthand safety considerations

We have taken great care to make sure that any widerissues (for example, spiritual, moral, ethical, social,legal, sustainable development, economic and culturalissues), including those relevant to the education ofcandidates at Key Stage 4, have been taken intoaccount when preparing this specification. They willonly form part of the assessment requirements wherethey are relevant to the specific content of thespecification. In Section 3 (Subject Content), aspectsof the wider issues that may be assessed areintroduced with the phrase: ‘Candidates should usetheir skills, knowledge and understanding to:’.Additionally, health and safety considerations areaddressed in the Controlled Assessment.

European Dimension

We have taken the 1988 Resolution of the Council ofthe European Community into account when preparingthis specification and associated specimen units.

Environmental Education

We have taken the 1988 Resolution of the Councilof the European Community and the ReportEnvironmental Responsibility: An Agenda for Furtherand Higher Education (1993) into account whenpreparing this specification and associatedspecimen units.

Avoiding Bias

We have taken great care to avoid bias of any kindwhen preparing this specification and specimen units.


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C Overlaps with other qualifications

The Unit 1 content of each of GCSE Biology, Chemistryand Physics is contained within GCSE Science A.

GCSE Science A covers similar content to GCSEScience B and both cover the programme of study.


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D The replacement of Key and Basic Skills with Functional Skills

Introduction

The Key Skills Qualification requires candidates todemonstrate levels of achievement in the Key Skills ofCommunication, Application of Number andInformation and Communication Technology.

The Wider Key Skills of Improving own Learning andPerformance, Working with Others and ProblemSolving are also available. The acquisition anddemonstration of ability in these ‘wider’ Key Skills isdeemed highly desirable for all candidates.

The units for each key skill comprise three sections:

■ What you need to know

■ What you must do

■ Guidance.

Candidates following a course of study based on thisspecification for Science A can be offered opportunitiesto develop and generate evidence of attainment inaspects of the Key Skills of:

■ Communication

■ Application of Number

■ Information and Communication Technology

■ Working with Others

■ Improving own Learning and Performance

■ Problem Solving.

Areas of study and learning that can be used toencourage the acquisition and use of Key Skills, and toprovide opportunities to generate evidence, areprovided in the Teachers’ Resource Bank for thisspecification.

The above information is given in the context of theknowledge that Key Skills at levels 1 and 2 will bereplaced by Functional Skills.

The replacement of Key and Basic Skills withFunctional Skills

The Key and Basic Skills qualifications will gradually bereplaced by Functional Skills(aqa.org.uk/functionalskills) which will be available incentres from September 2010. All Examination Officersin centres offering AQA Key Skills, Wider Key Skills andBasic Skills have been sent a letter outlining the detailsof the end dates of these subjects. Copies of theletters have also been sent to the Head of Centre andKey Skills or Basic Skills coordinator. This is a briefoutline of that information. It is correct as of October2010.

■ Key Skills Levels 1, 2 and 3 Test and Portfolio

The final opportunity for candidates to enter for a level1, 2 or 3 Key Skills test or portfolio will be June 2011with last certification in 2012. Centres are asked toensure that their funding is still available afteraccreditation ends on 31 August 2010. An exception isthat Key Skills in Apprenticeship Frameworks will beextended until March 2011. This will allow providersand employers the choice of offering either FunctionalSkills or Key Skills until 31 March 2011. For furtherinformation seehttp://nationalemployerservice.org.uk/news/story/extension-of-key-skills-for-apprenticeships

■ Key Skills Level 4

The last series available to candidates entering for theKey Skills Level 4 test and portfolio was June 2010with the last certification in the June series 2012.

■ Basic Skills Adult Literacy Levels 1 and 2,Adult Numeracy Levels 1 and 2

AQA Basic Skills qualifications will now be availableuntil the June 2012 series.

■ Wider Key Skills

The AQA Wider Key Skills qualifications in their presentform will continue to be available until June 2011.However, funding may be limited after June 2010.

Documents

GCSE Core Science