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Name : _______________________( ) 4551/2

Class : S5___

BIOLOGYPaper 2September 20122 ½ hours

SMJK PEREMPUAN CHINA PULAU PINANGTRIAL EXAM

2012

BIOLOGY PAPER 22 HOUR 30 MINUTES

DO NOT OPEN THIS BOOKLET UNTIL INSTRUCTED

This booklet consists of 16 printed pages.

Section TotalMarks

Marksobtained

A

1 12

2 12

3 12

4 12

5 12

B

6 20

7 20

8 20

9 20

Total 100

1. This question booklet consistsof two sections:Section A and Section B

2. Answer all questions. Writeyour answers for Section A inthe spaces provided in thisquestion booklet.

3. Write your answers for SectionB on the given lined paper.

4. The diagrams in the questionare not drawn to scale unlessstated.

5. If you wish to change youranswer, cross out the wronganswer and writedown your new answer.

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Section A [ 60 marks ]

Answer all questions in this section.

1. Diagram 1.1 shows stages A and stage B drawn from photomicrographs of mitosisin the root tip of a dicotyledonous plants.

A BDiagram 1.1

(a) Name the stage of mitosis in A and B.(i) A._________________________________________________________

(ii) B._____________________________________________

[ 2 marks ]

(b) (i) What is the diploid number of this dicotyledonous plants?_____________________________________________

[ 1 mark ]

(ii) Explain your answers in 1(b) (i).________________________________________________________________________________________________________________________________________________________________________________________________

[ 2 marks ]

X

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(c) How do the chromosomes arrange themselves before they separate tomove to the opposite poles?_______________________________________________________________________________________________________________________________________

[ 2 marks ]

(d) (i) What is structure X in Diagram 1.1 stage B?_____________________________________________

[ 1 mark ]

(ii) Why is structure X important in the process of cell division?__________________________________________________________________________________________

[ 1 mark ]

(e) Name one part of plant, other than root tips where cells undergoingmitosis could be found.__________________________________________

[ 1 mark ]

(f) Diagram 1.2 show an important event that take place during S phase incell cycle.

Diagram 1.2(i). Name the event that take place in Diagram 1.2._____________________________________________

[ 1 mark ](ii). State the outcome of this event._____________________________________________

[ 1 mark ]

A DNA double helix

Old strands

New strands

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2. Table 1 shows the recommended daily intakes of energy and nutrients fordifferent individuals.

IndividualChild

( 1 year old)Male

adolescentFemale

adolescentBody Weight (kg) 9.5 62.0 55.0

Energy (kJ ) 3000 12400 9300Protein (g) 20 80 60

Vitamin D (µg) 12 3.0 3.0Iron (mg) 6 12 14

Table 1

(a) Based on Table 1, explain why the male adolescent requires(i) only one-fourth of vitamin D required by the child____________________________________________________________________________________________

[ 1 mark ]

(ii) less iron than that required by the female adolescent.____________________________________________________________________________________________

[ 1 mark ](b) Calculate the daily protein requirement per kg of weight for the

(i) child______________________________________________

[ 1 mark ](ii) male adolescent______________________________________________

[ 1 mark ](c) Based on the protein requirements calculated in (b)(i) and (ii), explain

the difference between that required by the child and the maleadolescent.____________________________________________________________________________________________

[ 1 mark ]

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(d) For a person who does not take meat, explain why it is necessary forhim to include soya bean in his diet.__________________________________________________________________________________________

[ 2 marks ]Diagram 2.1 shows a incomplete schematic diagram to represent thelight reaction in photosynthesis.

Diagram 2.1

(e) State one main importance of light reaction.__________________________________________________________________________________________

[ 1 mark ](f) During the photolysis of water, hydrogen ions and hydroxyl ions are

produced. State the use of(i) hydrogen ions.__________________________________________________________________________________________

[ 2 marks ](ii) hydroxyl ions._______________________________________________________________________________________________________________________________________

[ 2 marks ]

12 H2O

Chlorophyll24 H

24 H2O

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3. Diagram 3.1 shows the respiratory structures structure of an organism.

Diagram 3.1(a) Which type of organism has the respiratory structure in Diagram 3.1?

_____________________________________________[ 1 mark ]

(b) (i) Name the structures labelled P and Q.P: ___________________________________________

Q: ___________________________________________[ 2 marks ]

(ii) What is the function of structure P?_____________________________________________

[ 1 mark ]

(c) Draw arrows ( ) to show the pathway of gaseous exchange inDiagram 3.1. [ 1 mark ]

(d) Explain the breathing mechanism of this organism during inhalationand exhalation.(i) Inhalation____________________________________________________________________________________________________________________________________________________________________________________

[ 2 marks ]

PQ

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(ii) Exhalation____________________________________________________________________________________________________________________________________________________________________________________

[ 2 marks]

Diagram 3.2 shows structure Q and body cell.

Diagram 3.2

(e)State three adaptations of structure Q.i. ______________________________________________________________________________________

ii. __________________________________________________________________________________________________

iii. ______________________________________________________________________________________

[ 3 marks ]

Q

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4. Diagram 4.1 shows the action of node P on human heart.

Diagram 4.1

(a) (i) Name the node P._____________________________________________

[ 1 mark ]

(ii) Based on Diagram 4.1, explain the function of node P.__________________________________________________________________________________________________________________________________________

[ 3 marks ]

(b) State where do the blood that flows blood vessel Q and in blood vessel Rflow to.(i) blood vessel Q.______________________________________________

[ 1 mark ](ii) blood vessel R.______________________________________________

[ 1 mark ]

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(c) Diagram 4.2(a) shows a healthy coronary artery.Diagram 4.2(b) shows the coronary artery of a person withcardiovascular disease. The coronary artery supply blood to heartmuscles.

Diagram 4.2(a) Diagram 4.2(b)

(i) Name deposit X.___________________________________________

[ 1 mark ]

(ii) Explain how the deposit X and thrombus lead to cardiovasculardisease._________________________________________________________________________________________________________________________________

[ 2 marks ](iii) Suggest three ways to maintain a healthy heart.i. ____________________________________________________________________________________

ii. ____________________________________________________________________________________

iii. ___________________________________________________________________________________

[ 3 marks ]

Thrombus X

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5. The pedigree inheritance of the characteristics, colour blindness in a familyin Diagram 5.1. The characteristic, colour blindness is controlled by apair of recessive allele bb that are linked to the sex chromosomes. B isdominant to b.

Diagram 5.1

(a) Explain briefly the characteristics, colour blindness.________________________________________________________________________________________

[ 1 mark ](b) (i) What is genotype of K?

____________________________________________[ 1 mark ]

(ii) How did you determine the genotype in (b) (i)?________________________________________________________________________________________

[ 2 marks ](c) (i) State the genotypes and gametes for the parent in the space

provided.

Female x MalePhenotype : Colour blind Normal

Genotype:

Gametes :

[ 2 marks ]

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(ii) If a colour blind male marries the third child in the thirdgeneration, what is the probability of obtaining children that are colourblind? Explain your answer by drawing a genetic diagram for thisinheritance.

[ 4 marks ]

(d) (i) Besides colour blindness, name another type of sex-linked diseasein humans that is controlled by a recessive alleles._____________________________________________

[ 1 mark ](ii) What is the characteristics for the disease given in (d)(i)?__________________________________________________________________________________________

[ 1 mark ]

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Section B [ 40 marks ]Answer any two questions from this section.

6. Diagram 6.1 shows a defence mechanism in the human body.

Diagram 6.1(a) (i) Explain how this mechanism works to combat pathogen.

[ 6 marks ](ii) Explain what will happen to the immunity of an individual afterhe recovers from chickenpox infection.

[ 4 marks ](b) Diagram 6.2 shows the human circulatory system.

Diagram 6.2(i) Human circulatory system consists of circulations R and S.Describe each circulation. [ 4 marks ]

(ii) After completing a 10 km run, Ali’s blood pressure increases.Explain the mechanism involved in regulation of Ali’s bloodpressure. . [ 6 marks ]

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7. A forest is an example of ecosystem. Diagram 7.1 shows a forest.

Diagram 7.1(a) Based on Diagram 7.1, what do you understand by the term

ecosystem ? Explain the components of the ecosystem.[ 4 marks ]

(b) (i) Diagram 7.2 shows one of the food chains in an ecosystem?

Plants Grasshopper Frog Snake

Diagram 7.2Based on the food chain above, explain how the organisms obtainenergy. [ 4 marks ](ii) Explain the role of plants in the food chain. [ 2marks ]

(c) Diagram 7.3 shows the colonization and succession of mangrove plantsin a mangrove swamp.

Diagram 7.3(i) State the type of mangrove plants and its roots which can be foundin Zones X, Y and Z respectively. [ 3 marks ]

(ii) Explain the adaptive characteristics of the mangrove plants inDiagram 7.3 which enable them to survive in the unfavourableenvironmental conditions in the mangrove swamp.

[ 7 marks ]

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8. Diagram 8.1 shows the negative feedback mechanism that regulates theblood glucose level in humans

Diagram8.1

(a) Based on Diagram 8.1,(i) Explain the meaning of negative feedback mechanism.

[ 4 marks ]

(ii) Describe how hormone X and Y regulate the blood glucose level inhumans.

[ 6 marks ]

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Diagram 8.2 shows some of the factors which regulate the carbon dioxidecontent in the body.

Diagram 8.2

(b) During vigorous exercise, increase in respiration leads to a rise inblood carbon dioxide levels. The structure P increases the breathingrate in response to this stimulus.

Based on the diagram, explain how the breathing rate takesplace in such situation.

[ 10 marks ]

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9. Diagram 9.1 shows a physiological process in humans.

Diagram 9.1(a) Describe the process shown in Diagram 9.1. [ 4 marks ](b)

A women faces difficulty in conceiving is injected with hormone X.Hormone X has similar role as luteinsing hormone (LH),. After theinjection with hormone X, the women becomes pregnant.

Based on the above information, explain how the injection withhormone X results in pregnancy. [ 6 marks ]

(c) Diagram 9.2(a) and 9.2(b) shows the katyotypes of a male and afemale. Number 1 to 22 are the autosomes and the sex chromes arenumbered as 23.

Diagram 9.2(a) 9.2(b)(i) Explain what is meant by autosomes and sex chromosomes.

[ 2 marks ](ii) State how sex chromosome differ from autosomes.

[ 3 marks ](iii) Describe how sex is inherited in humans.

[ 5 marks ]

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