1 Second termtest2012 GA Atoll School Biology/Grade8

Section:A

Choose the correct answer and underline with Pen

1. The arrows show the movement of salts into a cell.

Which describes the movement of the salts?

A. active transport against the concentration gradient

B. active transport down the concentration gradient

C. diffusion against the concentration gradient

D. diffusion down the concentration gradient

2. Where in the alimentary canal is most water absorbed?

A.colon B.ileum C.oesophagus D.stomach

3. Which food would be best for a person suffering from anemia?

4. The diagram shows the arrangement of teeth in the human jaw.

2 Second termtest2012 GA Atoll School Biology/Grade8

5. Milk produces a red precipitate when heated with Benedict’s solution.

A purple colour develops when the biuret test is used on milk.

Using these results only, which nutrients does milk contain?

A.fat and protein B.fat and starch

C.reducing sugar and protein D.reducing sugar and starch

6. What are some of the end products and effects of anaerobic respiration in muscle?

A.carbon dioxide and muscle contraction B.ethanol and loss of coordination

C.lactic acid and oxygen debt D.water and muscle relaxation

7. The diagram shows a section through an alveolus and an associated blood capillary.

In which part is the concentration of carbon dioxide highest?

8. Which graph shows the effect of temperature on the rate of photosynthesis?

3 Second termtest2012 GA Atoll School Biology/Grade8

9. Two samples of food are tested. The results are shown in the table.

What do these results show?

A. Sample 1 contains starch and sugars. B. Sample 1 contains starch only.

C. Sample 2 contains starch and protein. D. Sample 2 contains protein only.

10. The pH in the mouth decreases after eating.

Which statement explains the decrease in pH?

A. Bacteria release acids when respiring food substances.

B. Enzymes in saliva release acids during digestion.

C. Food substances become alkaline when chewed.

D. Salivary glands release an alkaline solution.

11. Large, insoluble molecules have to be digested before they can be

A. absorbed. B. assimilated. C. egested. D. ingested.

12. After muscular exercise, which blood vessel carries the most carbon dioxide?

A. aorta B. hepatic artery C. pulmonary vein D. vena cava

13. Which process, occurring in the human body, does not involve energy from respiration?

A. contraction of heart muscle B. diffusion of oxygen from the alveoli into the blood

C. digestion of bread D. maintaining a constant body temperature

14. Which changes occur as a person exercises?

15. Which organ is damaged as it breaks down alcohol?

A. brain B. kidney C. liver D. stomach

4 Second termtest2012 GA Atoll School Biology/Grade8

16. Vitamin C changes cholesterol into a form which is less likely to be deposited in artery walls. Which

dietary advice would help prevent coronary heart disease?

A. Eat more bread and less meat B.Eat more butter and less bread

C. Eat more meat and less oranges D.Eat more oranges and less butter

17. Which feature helps plants to make most food by the process of photosynthesis?

A. Spiky leaves B road and flat leaves

C. Shiny surfaced leaves D. Variegated leaves

18. In which regions of the alimentary canal does amylase act?

A. Mouth cavity and pancreas B .Mouth cavity and ileum

C. Stomach and pancreas D.Stomach and ileum

19. Which signs show that a plant has been grown in a culture solution deficient in magnesium?

A. Purple leaves and poor root growth B.Small leaves and thin stems

C. White upper leaves and normal lower leaves D.Yellow stem and yellow leaves

20. Bread contains dietaryfibre, fat, protein and starch.

Which substance contributes least to the energy obtained by a person eating the bread?

A. Dietary fibre B.Fat C.Protein D.Starch

21. Starch is digested to maltose by the enzyme amylase.

According to the ‘lock and key’ hypothesis, which is the ‘key’ and which is the ‘lock’?

5 Second termtest2012 GA Atoll School Biology/Grade8

22. The diagram shows a photosynthesis investigation. The plant has leaves that are green in the

middle and white round the edges.

Which leaf areas lack only one factor needed for photosynthesis?

A. P and Q B. P and R C. Q and S D. R and S

23. The table shows the nutrients in different parts of a meal.

Which food would be most useful in preventing constipation?

24. In which order do these events occur in human nutrition?

A. Digestion → ingestion → absorption → assimilation

B. digestion → ingestion → assimilation → absorption

C. ingestion → digestion → absorption → assimilation

D. ingestion → digestion → assimilation → absorption

25. Tennis players often eat bananas during long matches.

Which nutrient in a banana is important during the match?

A. carbohydrate B.fibre C. iron D. vitamin C

6 Second termtest2012 GA Atoll School Biology/Grade8

26. The table shows the percentage composition of a gas in inspired and in expired air.

What is the gas?

A. carbon dioxide B. nitrogen C. oxygen D. water vapour

27. Through which sequence does carbon dioxide pass as it leaves the lungs?

A. alveolar wall → in the alveoli → blood → capillary wall

B. blood → capillary wall → alveolar wall → in the alveoli

C. capillary wall → blood → in the alveoli → alveolar wall

D. in the alveoli → alveolar wall → capillary wall → blood

28. Which liquid has the highest water potential at atmospheric pressure?

A. distilled water B. leaf cytoplasm C. root hair cell sap D. soil water

29. Which one of the following chemical elements is needed for the proper growth of roots?

Calcium B. Iron C. Phosphorous D. Magnesium

30. Which processes can take place in a root hair cell when oxygen is not available?

A active transport only B diffusion only

C active transport and osmosis D diffusion and osmosis

7 Second termtest2012 GA Atoll School Biology/Grade8

Section B

Answer all the questions

1. Fig. 1.1 shows a section through a leaf with only some of the cells drawn.

Fig 1.1

(a) On Fig. 1.1, draw and label in their correct positions: [4m]

(i) a palisade mesophyll cell;(ii) a spongy mesophyll cell;

(iii) a pair of guard cells;(iv) a cuticle.

(b) On Fig. 1.1, label and name the tissue bringing water into the leaf.[1m]

(c) Suggest one reason why epidermal cells are important to a leaf.

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d) What are the special features of the palisade cell compared to the other cells in the leaf?

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[Total:10]

8 Second termtest2012 GA Atoll School Biology/Grade8

2. Fig. 2.1 shows a cell from an organism.

Fig2.1

(a) In which type of living organism are cells similar to the one shown in Fig.

normally found ................................................................................................................... [1m]

Fig. 2.2(a) shows the same cell after it had been placed in solution A for ten minutes. The

cell was then transferred to solution B and Fig. 2.2(b) shows how it appeared after a further

ten minutes.

Fig2.2(a) Fig2.2(b)

(b) Explain what has occurred to cause the cell to appear as it does in Fig. 2.2(a).

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................................................................................................................................................................ [3m]

(c) Compared with the water potential of the cell, what can be deduced about solutions AandB?

SolutionA...........................................................................................................................................

SolutionB......................................................................................................................................... [2m]

d) What will be found in region C in Fig. 2.2(b) at the end of the experiment?

......................................................................................................................................................... [1m]

Define osmosis.........................................................................................................................................

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[Total: 10 marks]

9 Second termtest2012 GA Atoll School Biology/Grade8

3.For the human to survive properly, a special diet is needed.

a) Define balanced diet.

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b) The pictures below shows some of the diseases caused due to lack of some nutrients.

i) Write the name of the disease and the deficient nutrient.

Fig:1 Fig: 2

Name :……………………… ……. Name:…………………………………

Nutrient:……………………………. Nutrient:……………………………….. [4m]

c.Explain the roles of liver in our body?

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[Total: 10 marks]

10 Second termtest2012 GA Atoll School Biology/Grade8

4.Fig. 4.1 shows the human alimentary canal.

a) Label all the parts. [5m]

Fig 4.1

(b) In which lettered part does most of the absorption of substances in solution occur?

............................................................................................................................................................... [1m]

c) In which lettered part does the fat digestion begins.

............................................................................................................................................................... [1m

d) Figure below shows some food as it moves along the small intestine.

i) Describe what is happening to the muscles in the wall of the small intestine at positions H and I, and

explain how this causes the food to

move.…………………………………………………………………………………………………………………

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ii) Define the process shown in the diagram.

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[Total: 10 marks]

11 Second termtest2012 GA Atoll School Biology/Grade8

5. Figure 5.1 below shows the respiratory surface.

Fig5.1

a) Define respiration.

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…………………………………………………………………………………………………[1m]

b) State the labeled parts shown in the diagram.

A……………………….. B………………………. C…………………………. [3m]

c) Define anaerobic respiration? Which are the end products?

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d) Explain the changes occurred to the rib muscle and the structure C when a person breathes in.

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[Total : 10 marks]

A

B

C

12 Second termtest2012 GA Atoll School Biology/Grade8

Section C

Answer any two question from this section

6.a) Describe how the action of enzymes can beexplained by lock and key hypothesis

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b)Describe and explain the effect of a gradual increase in temperature on an enzyme-controlled reaction.

You should refer to the ‘lock and key’ hypothesis.

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13 Second termtest2012 GA Atoll School Biology/Grade8

7.a) Describe a cell.

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b)Draw the diagram of plant cell and animal cell

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c)Differentiatexylem and phloem.

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[Total:10marks]

14 Second termtest2012 GA Atoll School Biology/Grade8

8.a) Describe about the concept of limiting factors

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b)Prove that light and carbondioxide are essential factors for photosynthesis

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