WAEC Biology Past Questions & Answers - Page 252

1,256.

Enzymes can be inactivated by certain chemical substances in the body called

A.

catalysts

B.

inhibitors

C.

substrates

D.

activators

Correct answer is B

No explanation has been provided for this answer.

1,257.

The colour that is associated with a positive iodine test is

A.

brown

B.

red

C.

blue-black

D.

yellow

Correct answer is C

No explanation has been provided for this answer.

1,258.

In a test for non-reducing sugars like sucrose, what is the significance of adding dilute hydrochloric acid to the original sugar solution? To

A.

hydrolyse the non-reducing sugar

B.

accelerate he rate of the reaction

C.

stabilize the medium

D.

sterilize the solution

Correct answer is A

No explanation has been provided for this answer.

1,259.

Biuret’s test is carried out on a food substance to indicate the presence of

A.

vitamins B

B.

fats

C.

proteins

D.

starch

Correct answer is C

No explanation has been provided for this answer.

1,260.

Micronutrients essential for the synthesis of chlorophyll include

A.

iron and potassium

B.

iron and magnesium

C.

magnesium and calcium

D.

magnesium and potassium

Correct answer is B

No explanation has been provided for this answer.