Biology Past Questions and Answers

(a) Explain briefly how the human ear carries out its function of balancing.<br/>(b) (i) make a drawing 8 cm - 10 cm long of the structure of the human ear and label fully.<br/>(ii) Describe briefly the structure of the middle ear in humans.<br/>

(a)(i) What is a deficiency disease?<br/>(ii) Complete the table below by naming five nutrient deficiency diseases in humans and stating one remedy for each of the diseases.<br/>(b) Outline a chemical test for (i) Starch in a tuber of yam (ii) Glucose in orange fruit<br/><table class='tbn'><tbody><tr><td> Nutrient deficiency disease </td><td> Remedy </td></tr><tr><td> </td><td> </td></tr><tr><td> </td><td> </td></tr><tr><td> </td><td> </td></tr><tr><td> </td><td> </td></tr><tr><td> </td><td> </td></tr></tbody></table><br/><br/><br/>

(a) Complete the table below;<br/><table class='tbn'><tbody><tr><td> Disease </td><td> Causative organism </td><td> Vector </td><td> Control </td></tr><tr><td> Cholera </td><td> </td><td> </td><td> </td></tr><tr><td> </td><td> Trypanosome </td><td> </td><td> </td></tr><tr><td> </td><td> </td><td> Female Anopheles mosquito </td><td> </td></tr><tr><td> Ringworm </td><td> </td><td> None </td><td> </td></tr></tbody></table><br/><br/><br/>(b) Explain briefly the biological basis of preserving foods using each of the following methods;<br/>(i) salting (ii) irradiation (iii) smoking <br/>

(a) Explain briefly; (i) independent assortment of genes (ii) the reason blood group O in humans can only exist in homozygous form while blood groups A and B can exist both in homozygous and heterozygous forms.<br/>(b) Complete the table below by naming the classes of vertebrates in their evolutionary trend and giving one example each of the classes.<br/><table class='tbn'><tbody><tr><td> Classes of vertebrate </td><td> One example </td></tr><tr><td> </td><td> </td></tr> <tr><td> </td><td> </td></tr><tr><td> </td><td> </td></tr><tr><td> </td><td> </td></tr><tr><td> </td><td> </td></tr></tbody></table><br/><br/><br/>

(a) Explain briefly the following types of fertilization in animals; (i) external fertilization (ii) internal fertilization <br/>(b) Name two groups of animal each that exhibit the types of fertilization in (a)<br/>(c)(i) If the placenta in a pregnant woman is detached from the uterine wall, give three effect this will have on the foetus <br/>(ii) Name three other features in the uterus of a pregnant woman that are useful for the development of the foetus<br/>(d) Explain briefly how the activities of organisms bring bout dynamic equilibrium in the habitat.<br/>(e) State four problems that organisms in the intertidal zone of a marine habitat could encounter.<br/>(f) Explain briefly the reasons that the following factors are necessary for germination; (i) moisture (ii) viable seeds <br/>(g) Explain briefly the reason light energy is considered a limiting factor in the production of foods by autotrophs.<br/>