2H₂ → 2H₂ + O_2(g). The equation above represents a part of the light stage of photosynthesis. Which of the following must be presents for this reaction to occur?

A. Enzyme and light energy

B. Carbondioxide and light energy

C. Light energy and cholorphyll

D. Chlorophyll and enzyme

In an experiment to investigate the effect of nitrogen on the growth of plants, the substrate should be a medium of

A. washed sand

B. saw dust

C. cow dung

D. clay soil

Which vitamin plays an important role in blood clotting?

A. vitamin A

B. Vitamin K

C. Vitamin B₁₂

D. Vitamin C

The mammalian organ which acts both as a digestive and as an endocrine organ is the

A. oesophagus

B. liver

C. pancreas

D. spleen

Which of following is NOT involved in the transport of substance in the body?

A. Lymph

B. Plasma

C. Leucocytes

D. Erythrocytes

The end product of glycolysis in plants and animals is

A. pyruvic acid

B. citric acid

C. aspartic acid

D. malic acid

During respiration, air circulates round plant tissues via the

A. lenticels

B. stomata

C. guard cells

D. intercellular spaces

The excretory structure in the earthworm is the

A. malpighian tubule

B. flame cell

C. nephridium

D. kidney

During the bending of the arm, the biceps muscles

A. contracts and the triceps muscles relaxes

B. relaxes and the triceps muscles contracts

C. and the triceps muscles contract

D. and the triceps muscles relax

When a healthy shoot of a flowering plant is illuminated from one side, auxins, accumulate on the

A. non-illuminated side of the shoot

B. illuminated side of the shoot

C. upper side of the shoot

D. lower side of the shoot