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SECTION A (20 marks)

Answer all questions. 1.

Figure 1

Figure 1 shows a leaf of a balsam plant covered with a piece of black paper. What is to be proven in this experiment? (A) Plants need air. (B) Plants need food. (C) Plants need water. (D) Plants need sunlight.

2. Fibrous food is required in our daily diet.

Which of the following statement is incorrect about fibrous food? (A) Fibrous food consists of cellulose. (B) Fibrous food prevents constipation. (C) Fibrous food contains high energy value. (D) Fibrous food promotes peristalsis in the intestine.

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3. Which of the following statements are the functions of proteins? I Acts as an antibody II Acts as an insulator III Acts as a biological catalyst IV Acts as an exoskeleton of insect V Acts as a storage substance in adipose tissue (A) I, II and III only (B) II, IV and V only (C) I, III and IV only (D) III, IV and V only 4.

Figure 2 Figure 2 shows how a plant cell and an animal cell are related. What is best represented by P? (A) Cell wall (B) Centriole (C) Chloroplast (D) Cell Membrane

Plant cell

Animal cell

P

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5. What type of muscle tissue suits the above description? (A) Smooth muscle (B) Cardiac muscle (C) Skeletal muscle (D) Voluntary muscle

• Spindle-shaped • Absence of striations • Lining of intestine canal • One nucleus centrally located

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6. Air pressure •

Time Figure 3

Figure 3 shows the changes in air pressure in the thoracic cavity during a breathing cycle. Which of the following does not happen at point P? (A) Air is drawn into the lung. (B) Diaphragm curves upwards. (C) External intercostal muscles contract. (D) The volume of the thoracic cavity increases.

P

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7. Which of the following structures in plants involve in gaseous exchange? I Xylem II Stoma III Cuticle IV Lenticel V Epidermis (A) II and IV only (B) III and IV only (C) I, II, and V only (D) I, III and V only 8. Cellular respiration in human can either be aerobic or anaerobic.

Which of the following indicates aerobic respiration?

Carbon dioxide

Water Lactic acid Heat released

A

None

None

Present

Little

B

None

Present

None

Little

C

Present

Present

None

Much

D

Present

Present

Present

Much

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9.

Figure 4

Figure 4 shows the structure of a mitochondria.

Where do the Krebs cycle and electron transport chain take place respectively?

(A) 1 and 2 (B) 1 and 3 (C) 2 and 3 (D) 2 and 4 10. Which of the following parameters can be used to measure growth? I Increase in mass II Increase in length III Increase in height

IV Increase in cell size

V Increase in cell numbers (A) IV and V only (B) I,II and IV only (C) I, II and III only (D) III, IV and V only

1

3

2

4

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11. Dry mass in grams Time in days

Figure 5

Figure 5 shows the relative changes in dry mass of endosperm and embryo during germination of barley seeds. Which of the following is the correct match for P, Q and R?

Total mass

Endosperm mass

Embryo mass

A

P

Q

R

B

P

R

Q

C

Q

P

R

D

R

Q

P

P Q

R

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12.

Figure 6 Figure 6 shows a part of the human digestive system. What will happen if duct X is blocked? (A) Fats will not be digested. (B) Starch will not be digested. (C) Proteins will not be digested. (D) Pancreas juice will not reach the stomach.

X

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13.

Figure 7

Figure 7 shows processes involved in photosynthesis. Which of the following substance represents P, Q, R and S?

Water

Carbon dioxide

Oxygen

Glucose

A

Q

P

S

R

B

P

Q

R

S

C

S

Q

R

P

D

P

S

Q

R

Light

R S

P Q

Light reaction

Dark reaction

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14. Which of the following statement is incorrect concerning the kidney function?

(A) Most water is reabsorbed at the distal convoluted tubule. (B) Glucose is reabsorbed at the proximal convoluted tubule. (C) Deamination of amino acids in the kidney cells results in the production of urea. (D) Blood leaving the kidney via renal vein contains less glucose than the blood in renal artery. 15. Which of the following statements are true about transpiration? I The water vapour diffuses through stoma . II The loss of water is in the form of water vapour.

III Light intensity will increase the rate of transpiration. IV Transpiration provides the cooling effect to the plants.

V Higher relative humidity will decrease the rate of

transpiration. (A) I, III and V only (B) II, III and IV only (C) I, II, III and IV only (D) I, II, III, IV and V only

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16. Which of the following shows the correct number of chromosome in each cell during spermatogenesis?

Spermatogonium

Primary

spermatocyte

Secondary

spermatocyte

A

Diploid

Diploid

Haploid

B

Haploid

Diploid

Diploid

C

Haploid

Haploid

Diploid

D

Haploid

Diploid

Haploid

17. G, H, I and J are the events in the sexual reproduction of a flowering plant. Which of the following is the correct order of events in the sexual reproduction of a flowering plant? (A) H J G I (B) G H J I (C) G J I H (D) J I G H

G - Pollen falls on the stigma and germinates. H - Pollen tube grows towards the micropyle. I - The male nucleus fuses with the female nucleus. J - The nucleus tube penetrates the wall of the embryo sac.

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18.

Figure 8 Figure 8 shows four muscles labelled as N, P, Q and R in the jointed leg of an insect. What will happen to the muscles if the leg bends into a ‘Z’ shape?

N

P

Q

R

A

Contract

Relax

Relax

Contract

B

Relax

Contract

Contract

Relax

C

Contract

Relax

Contract

Relax

D

Relax

Contract

Relax

Contract

N

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19. What are the characteristics of birds that enable them to fly? I streamlined body II strong solid bones

III light flight feathers

IV powerful flight muscle V an aerofoil shaped wings (A) I, III and V only (B) II, III and IV only (C) I, III, IV and V only (D) I, II, III, IV and V only 20. Which of the following situations are the taxis responses?

I Flower blooms at night II Root grows towards gravity III Legume leaves curl at night IV Euglena moves towards light V Amaeba moves towards food

(A) II and IV only (B) IV and V only (C) I, II and III only (D) III, IV and V only