HERZLIA MIDDLE SCHOOL

1 Grade 8 Natural Science End of Year Examination 2015 UHS

NAME TEACHER’S COMMENT

TEACHER

CLASS

MARK

PERCENTAGE

HERZLIA MIDDLE SCHOOL

NATURAL SCIENCES

GRADE 8

END OF YEAR EXAMINATION

27 NOVEMBER 2015

TIME: 90 Minutes

MARKS: 150


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INSTRUCTIONS:

1. This paper consists of 22 pages. Check that you have them all.

2. Answer all the questions on this paper in blue or black ink.

3. All diagrams and graphs should be done in pencil and labelled in ink.

4. Read each question carefully before answering it and pay attention to the mark

allocation.

5. Write neatly and legibly.


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MULTIPLE CHOICE ANSWER SHEET

NAME: ______________________________ CLASS: _____

Multiple Choice (use pencil only)

Choose the answer, which you consider most appropriate and cross the corresponding letter on this Answer Sheet.

E.g. If your answer to 1.3 is D, indicate your choice like this:

1.3 A B C D

If more than one cross appears in any line, the answer will be marked wrong.

1.1 A B C D

1.2 A B C D

1.3 A B C D

1.4 A B C D

1.5 A B C D

1.6 A B C D

1.7 A B C D

1.8 A B C D

1.9 A B C D

1.10 A B C D


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SECTION A: SHORT QUESTIONS QUESTION 1: MULTIPLE CHOICE Four options are provided as possible answers to the following questions. Each question has only ONE correct answer. Cross the letter (A-D) next to the question number (1.1 – 1.10) on the ANSWER SHEET. [20] 1.1 The smallest particle that make up matter (2)

A molecule

B compound

C atom

D element

1.2 The imbalance of charges in a material is (2)

A current

B resistance

C electrostatic

D power

1.3 A substance that does not allow visible light to pass through (2)

A transparent

B translucent

C opaque

D reflector

1.4 The bending of light due to a change in medium (2)

A refraction

B reflection

C deflection

D dispersion

1.5 Substance that does not allow the flow of electrons easily (2)

A conductor

B insulator

C metal

D plastic


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1.6 Which two types of microorganisms form an association that we know as lichen? (2)

A alga and bacteria

B fungi and bacteria

C alga and fungi

D alga and protists

1.7 Malaria is a disease cause by a (2)

A virus

B protist

C bacterium

D fungus

1.8 Thread-like structures on a fungus are known as (2)

A mycelium

B hyphae

C prokaryotes

D budding

1.9 In an ecosystem, fungi are (2)

A predators

B producers

C decomposers

D omnivores

1.10 An aquatic protist occasionally infects the skin and gills of a fish belonging to the

carp family. This protist causes the death of the fish, after which it continues to live and grow on the surface of the dead body. The terms used to describe the mode of nutrition of the organism before, and after causing the death of the fish, are: (2)

A autotrophic then saprophytic

B parasitic then saprophytic

C heterotrophic then parasitic

D saprophytic then parasitic


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QUESTION 2: TERMINOLOGY Give one word/term for each of the following descriptions. Write only the word/term on the line below the statement. Do not give examples. [10] 2.1 Body of hot, glowing gases in the space that produces its own energy. (1) ________________________________________________________________ 2.2 Rounded body travelling around a star in a clear circular path. (1) ________________________________________________________________ 2.3 It is the furthest planet from the Sun. (1) ________________________________________________________________ 2.4 Smaller piece of rock in space, smaller than an asteroid. (1) ________________________________________________________________ 2.5 Collection of all colours that make the rainbow. (1) ________________________________________________________________ 2.6 Process in which an ionic substance is broken down into simpler elements. (1) ________________________________________________________________ 2.7 A circuit that allows current to flow in one path. (1) ________________________________________________________________ 2.8 A blue substance that produces chlorine gas when current passes through it. (1) ________________________________________________________________ 2.9 What transforms the potential energy in a cell into another form of energy? (1) ________________________________________________________________ 2.10 Word to describe an object that gives off light or glows in the dark. (1) ________________________________________________________________


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QUESTION 3: MATCHING COLUMNS Choose a word or phrase from COLUMN B that matches a word or phrase in COLUMN A. Write only the letter (A – M) next to the question number (3.1 – 3.10). [10]

COLUMN A COLUMN B

3.1 ___ Diagrammatic representation of an electrical circuit

A Nuclear reactor

3.2 ___ A resistant wire used in bulbs B nanometres

3.3 ___ Regions of force surrounding a magnet C ionic

3.4 ___ A solution with positively and negatively charged particles

D blue

3.5 ___ A device to protect electrical components E bacilli

3.6 ___ Light with the longest wavelength F field

3.7 ___ Natural force of every object that attracts other objects to itself

G fuse

3.8 ___ Atoms of Hydrogen gas continuously reacting H micrometres

3.9 ___ Bacteria that are rod-shaped I Magnetic force

3.10 ___ Units measuring size of viruses J red

K gravity

L circuit

M filament


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SECTION B: ENERGY AND CHANGE [67] QUESTION 1: STATIC ELECTRICITY [9] 1.1 Explain why a child’s hair stands up after playing inside the plastic tube. (4) _______________________________________________________________

_______________________________________________________________

_______________________________________________________________

_______________________________________________________________

1.2 Look at the image below and answer the questions that follow. 1.2.1 What causes an electric spark? (2) _______________________________________________________________

_______________________________________________________________

1.2.2 When do the sparks caused by static electricity become harmful? (1) _______________________________________________________________

_______________________________________________________________


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1.2.3 List 2 ways to prevent a person from being struck by lightning. (2) _______________________________________________________________

_______________________________________________________________

_______________________________________________________________

QUESTION 2: VISIBLE LIGHT [32] 2.1 The picture below shows a rainbow. Explain in detail how a rainbow is formed. You can use diagrams to demonstrate

your explanation. (4) _______________________________________________________________

_______________________________________________________________

_______________________________________________________________

_______________________________________________________________

_______________________________________________________________

_______________________________________________________________

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2.2 A torch shines on a cardboard box and creates a shadow and some of the light is reflected. On the diagram above, draw the light rays and label the following: Source of light; opaque object; reflected light; solid wall (screen) and shadow. (6) 2.3 Explain how absorption helps us to see different colours of materials or objects. (2) _______________________________________________________________

_______________________________________________________________

_______________________________________________________________

2.4.1 How is light reflected? (1) _______________________________________________________________

_______________________________________________________________

2.4.2 How does the angle of the light travelling to the mirror compare to the angle of

the reflected light? (1) _______________________________________________________________

_______________________________________________________________


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Mirror A

Mirror C

Incident ray

2.4.3 Solve the mirror maze below. (2)


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2.5 Read the text passage below and answer the questions.

The eyes and brain work together to enable human vision. The eyes collect and

focus visible light. The lens and other structures of the eye work together to focus a real image on the retina. The image is upside-down and reduced in size. Rods and cones in the retina send electrical signals about the image to the brain through the optic nerve. The brain interprets the signals as shape, colour, and brightness. It also interprets the image as though it were right-side up. The brain does this automatically, so what we see is always right-side up. The brain also “tells” us what we are seeing.

2.5.1 What is the role of the eyes in vision? (2) _______________________________________________________________

2.5.2 How does information about an image on the retina reach the brain? (2) _______________________________________________________________

_______________________________________________________________

2.5.3 What is the role of the brain in vision? (2) _______________________________________________________________

_______________________________________________________________


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2.6.1 Study the following ray diagrams that show the different types of lenses and answer the questions that follow. Name each lens and complete the ray diagrams. (6)

DIAGRAM A

DIAGRAM B 2.6.2 Give a specific use for each lens and explain why it is suitable. (4) Lens A: _________________________________________________________

_______________________________________________________________

Lens B: _________________________________________________________

________________________________________________________________


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QUESTION 3: ELECTRICAL SYSTEMS [26] 3.1 Draw a circuit diagram with the following components 2 bulbs in series, an open switch, and 2 cells in parallel (5) 3.2 In an investigation to find out the effect of the length of wire on the brightness of

a bulb, Grade 8C set up an experiment with the following: 3 cells, cell holder, different lengths of nichrome wires, a bulb, a switch. 3.2.1 Give an aim for this investigation. (1) _______________________________________________________________

3.2.2 Suggest a hypothesis for Grade 8C’s investigation. (2) _______________________________________________________________

_______________________________________________________________

3.2.3 Suggest 3 possible controlled variables. (3) _______________________________________________________________

_______________________________________________________________

_______________________________________________________________

3.2.4 Identify the independent and dependent variable of the investigation. (2) _______________________________________________________________

_______________________________________________________________


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3.3 Electrical current can be used to separate compounds by passing current through them using Hofmann voltameter. The following apparatus was set up to decompose water into oxygen and hydrogen. The volumes of substances in both sides were measured and recorded in a table.

3.3.1 Provide the name for general parts C and D which are present in the setup of

electrolysis investigations: ___________________________ (1) Table of results showing volumes of substances A and B respectively.

Time (minutes) 0 1 2 3 4 5 6 7 8 9

Volume of bubbles (ml)

A 0 0.6 1.2 1.5 1.6 1.7 1.8 1.9 2.0 2.2

B 0 0.3 0.6 0.75 0.8 0.85 0.9 0.95 1.0 1.1

B A

C D


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3.3.2 Draw a line graph below using the information in the table. Remember to apply all the rules for drawing graphs. NB: no colour! (9)

3.3.3 Compare and contrast the line graphs. (3) _______________________________________________________________

_______________________________________________________________

_______________________________________________________________


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SECTION C: EARTH AND BEYOND QUESTION 1: ASTRONOMY [12] 1.1 Place the following in order from biggest to smallest. (1) Asteroids, Jupiter, Solar system, Sun, Earth ________________________________________________________________ 1.2 Name the 8 planets in order of the furthest from the Sun to the closest. (2) ________________________________________________________________ 1.3 Write a short paragraph to explain why the Earth is ideal for life to exist. (3) _______________________________________________________________

_______________________________________________________________

_______________________________________________________________

1.4 Study the picture below. 1.4.1 What is the name of the group of the first four planets? (1) ________________________________________________________________ 1.4.2 What is the name of the group of the last four planets? (1) ________________________________________________________________ 1.4.3 Suggest a reason why all the objects in the solar system revolve around the

Sun. (2) _______________________________________________________________

_______________________________________________________________


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1.4.4 Name the galaxy in which the solar system is situated and state what shape of galaxy it is. (2)

_______________________________________________________________ SECTION D: LIFE AND LIVING QUESTION 1: MICROORGANISMS [31]

1.1 Read the following sources and answer the questions that follow. SOURCE A SOURCE B

[SECTION B TOTAL: 60]

[PAPER 1 TOTAL: 100]

Rabies has a worldwide distribution. 55 000 people die annually (31 000 in Asia and 24 000 in Africa.) Most infections are a result from a bite from an infected dog, except in South America where wild animals especially bats are responsible. 515 cases of rabies have been notified in humans in SA since 1928. Of these 515 cases, 344 are from dog contact, 29 from Yellow mongooses, 11 from genets and other wild cats, 15 from domestic cats, 2 from bats, and one each from a jackal, an ox, a caracal, a honey badger and a Chacma baboon; 108 from unknown sources. There were five confirmed cases of human rabies in 2009 where as in other years the statistics are in 2008: 16, 2007: 14, 2006: 32, and 2005: 7.

~ Human epidemiology of rabies in South Africa. Abstract of Presentation at Rabies seminar 22 September 2009

A Cure for Rabies? The survival of a Wisconsin teenager who contracted rabies may point the way to a treatment for this horrifying disease By Rodney E. Willoughby Jr.

Rabies is one of the oldest and most feared diseases. It attacks the brain, causing agitation, terror and convulsions. Victims suffer painful throat spasms when they try to drink or eat. Paralysis follows, yet people infected with rabies are intermittently alert until near death and can communicate their fear and suffering to family and caregivers. Although vaccines against rabies can prevent the illness from developing, until recently doctors could hold out no hope for patients who failed to get immunized soon after being bitten by a rabid animal. Once the symptoms of rabies appeared--typically within two months of the bite--death was inevitable, usually in less than a week. In 2004, however, I was a member of a team of physicians at Children's Hospital of Wisconsin in Milwaukee that rescued a 15-year-old girl from a similar fate. Jeanna Giese of Fond du Lac, Wisconsin, became the first known unimmunized survivor of rabies. (Five other people who had been immunized but developed rabies anyway have also survived.) Our novel treatment, dubbed the Milwaukee protocol, has stirred controversy among medical specialists; some claim that Jeanna's cure was a fluke*. Although the few attempts to replicate the treatment have not saved the lives of any other rabies patients, I fervently hope that we are on the right track.

*fluke: stroke of good luck; an accident

http://www.scientificamerican.com/author/rodney-e-willoughby-jr


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SOURCE C Refer to Source A for Questions 1.1.1 to 1.1.6 1.1.1 Name one way a human can be infected by rabies. (1) _______________________________________ 1.1.2 What effect does rabies have on the body? (2) _______________________________________________________________

_______________________________________________________________

1.1.3 Source A states that rabies kills 55 000 people annually and the majority of

cases are in Asia and Africa. Provide one possible reason why the distribution of rabies is more common in these parts of the world. (2)

_______________________________________________________________

_______________________________________________________________

1.1.4 What trend can be seen regarding the cases of human rabies from 2005 to

2009? (2) _______________________________________________________________

_______________________________________________________________

Medical history has shown most rabies deaths are caused by temporary brain dysfunction with little to no damage occurring to the brain itself. Using this information, Willoughby's team devised an experimental treatment for rabies. Giese's parents agreed to the experimental treatment. Willoughby's goal was to put Giese into an induced coma to essentially protect her from her brain, with the hope she would survive long enough for her immune system to produce the antibodies to fight off the virus. Giese was given a mixture of ketamine and midazolam to suppress brain activity, and the antiviral drugs ribavirin and amantadine, while waiting for her immune system to produce antibodies to attack the virus. Giese was brought out of the coma after six days, once signs of the immune system's progress became apparent.

http://en.wikipedia.org/wiki/Induced_coma

http://en.wikipedia.org/wiki/Ketamine

http://en.wikipedia.org/wiki/Midazolam

http://en.wikipedia.org/wiki/EEG

http://en.wikipedia.org/wiki/Antiviral_drug

http://en.wikipedia.org/wiki/Antiviral_drug

http://en.wikipedia.org/wiki/Ribavirin

http://en.wikipedia.org/wiki/Amantadine

http://en.wikipedia.org/wiki/Immune_system

http://en.wikipedia.org/wiki/Antibodies

http://en.wikipedia.org/wiki/Virus


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1.1.5 Using source A, tabulate the number of rabies cases caused by various sources of infection. (8)

1.1.6 In source A, it states 515 cases of human rabies have been recorded in South

Africa since 1928. Of those 515 cases, 344 are from dog contact. Calculate the percentage of recorded human cases of rabies that were a result from a dog contact. (2)

_______________________________________________________________

_______________________________________________________________

Refer to Source B and C for Question 1.1.7 to 1.1.9. 1.1.7 The Milwaukee Protocol involves inducing a coma in the rabies sufferer. In your

own words, describe the intended benefit this treatment hopes to achieve? (4) _______________________________________________________________

_______________________________________________________________

_______________________________________________________________

_______________________________________________________________


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1.1.8 Name the physician, credited with the Milwaukee Protocol treatment. (1) ________________________________________________________________ 1.1.9 Critics of the Milwaukee Protocol state the survival of Jeanna Giese, who

received this treatment, was a fluke. Do you agree with this? Provide an argument for your answer. (3)

_______________________________________________________________

_______________________________________________________________

_______________________________________________________________

_______________________________________________________________

1.2 Study the diagram below of a bacterium and answer the questions.

1.2.1 Use the scale line to calculate the actual length (A to B) of this bacterium. (2) _______________________________________________________________

_______________________________________________________________

_______________________________________________________________

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1.2.2 In a paragraph, identify and discuss two beneficial uses of bacteria. (4) _______________________________________________________________

_______________________________________________________________

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