JAMB Biology Past Questions & Answers - Page 371

1,851.

Viruses are considered to be living organisms because they

A.

possess transmittable characters

B.

move from one place to another

C.

respond to stimulation

D.

ingest food materials

Correct answer is A

No explanation has been provided for this answer.

1,852.

Farmers practise crop rotation because it

A.

helps to prevent soil erosion

B.

allows two crops to be planted at the same time

C.

helps to conserve soil fertility

D.

is an alternate to shifting cultivation

Correct answer is C

Crop rotation is a practice used to maintain nutrients in an agricultural soil.

1,853.

Most irrigated lands often become unproductive in later years because of

A.

loss of fertility

B.

increase in salinity

C.

soil erosion

D.

loss of water

Correct answer is C

Disadvantages of irrigation:

-  Excess water in the soil leads to waterlogging

1,854.

5 g of oven dried soil was heated in a furnace for 24 hours. After cooling, it weighed 4.8 g. What is the amount of humus in the soil?

A.

40.0g per 100 g dry soil

B.

4.4g per 100g dry soil

C.

4.0 g per 100g dry soil

D.

0.4g per 100g dry soil

Correct answer is C

No explanation has been provided for this answer.

1,855.

Which of the following is a dangerous product of coal burning?

A.

Sulphur dioxide

B.

Carbon dioxide

C.

Carbon

D.

Nitrogen

Correct answer is A

No explanation has been provided for this answer.