KNEC KCSE BIOLOGY TOPICAL QUESTIONS AND ANSWERS

The graph below represents a population growth of a certain herbivore in grassland ecosystem over a period of time.

3/8/2020

Comments

Suggest three factors that could have caused the population change between C and D.

Comments

The table below shows a list of five human diseases. Complete the table by naming the causative agent of each.

3/8/2020

Comments

The first one has been completed for you.

The table below shows a list of five human diseases. Complete the table by naming the causative agent of each.

Comments

State how excessive use of pesticides may affect soil fertility.

3/8/2020

Comments

Pesticides may kill soil micro-organisms that decompose humus to release mineral salts. In this
way they interfere with nutrient cycling.

how excessive use of pesticides may affect soil fertility

Overuse of chemical fertilizers and pesticides have effects on the soil organisms that are similar to human overuse of antibiotics. Indiscriminate use of chemicals might work for a few years, but after awhile, there aren't enough beneficial soil organisms to hold onto the nutrients” (Savonen, 1997).

Comments

ECOLOGY: Topical Biology Questions and answers

3/8/2020

Comments

1. 1989 Q4 P1
State how excessive use of pesticides may affect soil fertility
2. 1989 Q8 P1
The table below shows a list of five human diseases. Complete the table by naming the causative agent of each.
The first one has been completed for you.

Human Diseases

Comments

The graph below represents a population growth of a certain herbivore in grassland ecosystem over a period of time.

The table below shows a list of five human diseases. Complete the table by naming the causative agent of each.

State how excessive use of pesticides may affect soil fertility.

ECOLOGY: Topical Biology Questions and answers

TOPICS

Form 2

Form 3

Form 4

Archives

Categories