Waec Biology Past Questions and Answers

Question 36:

• WAEC 1989

Which of the following characteristics is associated with commensalism?

A. Both organisms are harmful to each other
B. The association involves many organisms
C. The association is beneficial to one of the organisms
D. Both species are beneficial to each other
E. This relationship is found only among higher plants

Question 37:

• WAEC 1989

Which of the following statements is not correct about the ecological effects of agricultural activities?

A. The use of herbicides and pesticides in farms can cause pollution
B. Bush-burning encourages desertification
C. Excessive use of fertilizers in farms may have harmful effects
D. Tillage of tropical soils with ploughs and harrows may encourage erosion
E. Monocropping is one of the cultural methods of controlling pests.

Question 38:

• WAEC 1989

Pests can be controlled without the subsequent danger of polluting the ecosystem by

A. Introducing a population of species similar to that of the pest
B. Increasing the population of the natural enemies of the pest
C. Eliminating the natural enemies of the pest
D. Keeping the population of natural enemies of the pest constant
E. Spraying the ecosystem with pesticide

Question 39:

• WAEC 1989

The activities of an organism which affect the survival of another organism in a habitat can be described as

A. Biotic factors
B. Climatic factors
C. Physiographic factors
D. Edaphic factors
E. Abiotic factors

Question 40:

• WAEC 1989

Which of the following. groups of organisms feeds directly on green plants?

A. Producer
B. Decomposer
C. Primary consumer
D. Secondary consumer
E. Tertiary consumer