Waec Biology Past Questions and Answers

Question 226:

• WAEC 1992

A climax community is characterised by

A. A stable composition of plant and animal species
B. Rapid changes in the composition of species
C. Constant changes in appearance of the habitat
D. Different species occurring at different times
E. Gradual change in animal population

Question 227:

• WAEC 1992

Which of the following is not a characteristic of overcrowding in plant and animal community?

A. Population outstripping available space
B. Population exceeding available food
C. Competition within the population
D. Increase in primary production
E. Population increasing at the same rate as the bith rate

Question 228:

• WAEC 1992

The use of predators or parasites to control pests in the farm is known as

A. Predator control
B. Chemical control
C. Biological control
D. Animal control
E. Parasitic control

Question 229:

• WAEC 1992

Which of the following substances cannot control the growth of harmful microoganisms?

A. Antibiotics
B. Hypertonic salt solution
C. Disinfectants
D. Isotonic sugar solution
E. Antiseptics

Question 230:

• WAEC 1992

Which of the following is the underling principle in the adoption of biological control of pests?

A. Knowledge of agricultural practices by the farmer
B. Relationship between plants and animals
C. The presence of poisonous chemicals in the farm
D. The relative population of plants and animals in the farm
E. The predator-prey relationship in the ecological community