WAEC Past Questions and Answers - Page 3671

18,351.

In a Biuret test, some protein was mixed with sodium hydroxide solution. Which of the following chemicals should be added to the mixture for a positive result?

A.

mercurous nitrate

B.

copper sulphate

C.

sodium carbonate

D.

silver nitrate

Correct answer is B

No explanation has been provided for this answer.

18,352.

A meal consisting of yam and a lot of vegetables is not balanced because it does not contain

A.

carbohydrates

B.

proteins

C.

vitamins

D.

minerals

Correct answer is B

No explanation has been provided for this answer.

18,353.

Why poor soil is treated with lime is to increase the quantity of

A.

nitrogen

B.

phosphorus

C.

carbohydrates

D.

sulphur

Correct answer is A

No explanation has been provided for this answer.

18,354.

The amount of starch in a germinating seed decreases because the starch is used up

A.

for respiration and to build cells

B.

to build a cellulose cell wall

C.

to develop meristematic tissues

D.

to produce enzymes

Correct answer is A

No explanation has been provided for this answer.

18,355.

Older parts of plant roots do not normally absorb water because

A.

they lack xylem

B.

they have a small surface area

C.

the phloem is dead

D.

they lack root hairs

Correct answer is D

No explanation has been provided for this answer.