Gce 2021 biology

1-A) Make a fully labeled drawing of the stomach of a named ruminant.

B) Briefly describe how a name herbivore is adapted for mechanical and chemicals digestion of cellulose.

C) How are the products of cellulose digestion absorbed and used.

2-A) Explain the following terms as use in reproduction.

a) Pathernogenesis

b) Capacitation

c) Cortical reaction

d) Ovulation

B) Describe the process of spermatogenesis in humans.

C) Hiw is spermatogenesis hormonally controlled in human?

3- A) What is a pollutant?Give three examples.

B) Described briefly the hazards of water and air pollution.

C) Differentiate between biodegradable and non-biodegradable pollutants giving at least one example of each.

4-A) outline

a) Mendel’s first law of inheritance.

b) Mendel’s second law of inheritance.

B) Explain,using appropriate genetic symbols,the possible blood groups of children whose father is heterozygote blood group A and mother heterozygote blood group B.

C) if these parents have two children, what is 5he probability that both will have blood group A?

5- Nucleic acid (DNA and RNA) are important components in the synthesis of protein in living organisms.

A) Compare DNA and RNA

B) Describe the events that occur in the translation of mRNA into polypeptides in cells.

6- A) Make a large fully labeled drawing of the cross-section of the human eye.

B) Identify the problem involved in the following eye effects and their methods of corrections.

a) Long-sightedness(Hypermetropia)

b) short-sightedness(Myopia).

C) explain the mechanism of color visions in humans.

7-A) Outline the mechanism of the uptake of the following by plants:

a) Water

b) Inorganic ions

B) How are organic substances transported and used in flowering plants.

8-A) What is genetic engineering.

B) Use a flow diagram to show some of the key stages which are typically involved in settings up a biotechnological process.

C)