Waec Agricultural Science 1989 Past Questions and Answers

Question 11:

• WAEC 1989

Nitrogen is made available to plants in the form of nitrates through the process of

A. Deamination and nitrification
B. Ammonification and denitrification
C. Deamination and ammonification
D. Nitrification and dentrification
E. Nitrification and ammonification

Question 12:

• WAEC 1989

Which of the following is not an effect of burning on the soil?

A. Increasing the organic matter in the soil
B. Increasing the soil nutrients
C. Increasing the acidity of the soil
D. Exposing the soil to erosion
E. Sterilization of the soil

Question 13:

• WAEC 1989

The function of soil micro-organisms include the following except

A. Decomposition of dead plant and animal remains
B. Recycling of nutrients
C. Causing plant or animal diesases
D. Living as parasites on crop plants
E. Filtration of soil water for plant use

Question 14:

• WAEC 1989

Slate is derived from

A. Schist
B. Sandstone
C. Shale
D. Gneiss
E. Quartzite

Question 15:

• WAEC 1989

The following are advantages of the sprinkler method of irrigation except

A. Rate of application of irrigation water can be controlled
B. Portable nature of many sprinkler system make them suitable for use
C. The sprinkler system can be made automatic
D. Method can be where topography affects horrowing of land
E. Method may be difficult for local farmers to use