SECTION A
ANSWER THREE QUESTIONS FROM THIS
1a. Draw a large and neatly labeled diagram of motor neurone.
b. Briefly describe how a nerve impulse is transmitted along a motor neurone.
c. Difine the term reflex action, giving an example.
2a. How does blood function as a transport medium?
b. Describe the mechanism of blood clothing on the side of a wound.
c. A woman who is Rh negative marries a man who is Rh positive.
i. Explain what hapens if her first baby is Rh positive.
ii. Explain what happens to the subsequent pregnancies.
3a. Define the following words:
i. Sexual intercourse
ii. Fertilization
iii. Sex-link genes
b. What are the disadvantages of feeding babies with cow milk?
c. List the signs and symtoms of sexual maturity in humans.
4a. Distinguish between the following pairs of words:
i. Antigens and antibodies.
ii. Active immunity and passive immunity.
b. How is the body naturaly protected from invading pathogens and harmful substances?
c. Suggest why it has not been possible to produce a vaccine for maleria.
SECTION B
ANSWER TWO QUESTIONS FROM THIS SECTION
5a. How is water useful in the body of humans?
b. Describe the process in which water id purified in a large scale.
ci. What is an intermittent water supply?
ii. State the causes of intermittent water supply in Cameroon.
6a. With the aid of an illustrated diagram ONLY, Show how nitrogens circumates in nature.
b. Define the following ecological terms:
i. An ecosystem
ii. A community
iii. A population
c. Explain he role of primary producersand decomposers in an ecosystem.
7a. Distinguish between refuge and sewage.
b. Briefly explain the following methods of refuge collection and disposal
c. State the harmful effects of untreated sewage.
Recent findings in social studies reveal that in a majority of post primary intitutions, there is a constant rising rate of teenage parenhood. The female students are most affected ; as they find them selves with un wanted pregnancies. These student expectant mothers usually keep away from regular monthly clinic attendance untill delivery.
As a result of this neglect, most of them end up with a Caesarian section. Worse still, they would be expected to attend monthly clinics after child birth. What an ordeal due to carelessness.