Question 636:

• JAMB 1989

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

Question 637:

• JAMB 1989

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

Question 638:

• JAMB 1989

Which of the labelled parts is used for feeling?

A. 1
B. 2
C. 3
D. 4

Question 639:

• JAMB 1989

The structure labelled 2 is the

A. Compound eye
B. Ocellus
C. Antenna
D. Labial palp

Question 640:

• JAMB 1989

Which of the structure is the molar?

A. 1
B. 2
C. 3
D. 4