Question 391:

• JAMB 1984

Denitrifying bacteria in nature liberate gaseous nitrogen directly from

A. Ammonium salts
B. Soil nitrates
C. Thunderstorms
D. Soil nitrites
E. Plant and animal proteins

Question 392:

• JAMB 1984

Leaching is

A. Washing away of humus from the soil surface
B. Reducing of soil aeration by pressure
C. Soil erosion by means other than rainfall
D. Loss of organic matter due to exposure to direct sunlight
E. Washing out chalk and limestone from upper layers of by heavy rains

Question 393:

• JAMB 1984

The process of soil erosion is usually from

A. Rill → sheet → gully
B. Gully → rill → sheet
C. Sheet → guly → rill
D. Sheet → rill → gully
E. Rill → gully → sheet

Question 394:

• JAMB 1984

The structure above represents a quill feather. The structure labelled 'M' is the

A. Quill
B. Rachis
C. Superior umbilicus
D. Inferior umbilicus
E. Aftershaft

Question 395:

• JAMB 1984

The young chick is formed from

A. 3
B. 3 and 4
C. 1, 3 and 5
D. 2
E. 4