CSEC Biology · May/June 2016 · Paper 2

38 questions and parts from this paper. Open one to see it in full, then practise it on Quelpr and get it marked against the mark scheme.

1. 1(a)(i)4 marksPlot a graph on the grid provided on page 5 to show the relationship between the number of oxygen bubbles released and temperature.
2. 1(a)(ii)1 markFrom your graph, determine the optimum temperature for the enzyme.
3. 1(a)(iii)6 marksExplain the shape of the graph at EACH of the following temperature ranges: 0-10 °C, 11-40 °C, > 40 °C
4. 1(a)(iv)1 markWrite a conclusion that the students could draw from their results.
5. 1(a)(v)1 markSuggest ONE reason why living organisms need to maintain a constant internal temperature.
6. 1(a)(vi)2 marksDescribe TWO precautions that the students should take when doing this experiment.
7. 1(a)(vii)2 marksHow could this experiment be modified to investigate the effect of pH on enzyme activity?
8. 1(b)2 marksName TWO enzymes that function in protein digestion and describe the role of EACH.
9. 1(c)(i)2 marksName TWO parts of the alimentary canal that are responsible for the mechanical digestion of food.
10. 1(c)(ii)2 marksGive TWO reasons why mechanical digestion of food is important.
11. 1(c)(iii)2 marksExplain the significance of chemical digestion of food.
12. 2(a)(i)3 marksIn the box provided below, draw a food web consisting of the following organisms: Algae, Small fish, Tadpole, Water snake, Egret, Eagle.
13. 2(a)(ii)1 markWhat is the role of the organism at the start of the food web?
14. 2(a)(iii)a)1 markName the organism which performs EACH of the following functions in the food web drawn in (a) (i) on page 10: Both as a prey and a predator.
15. 2(a)(iii)b)1 markName the organism which performs EACH of the following functions in the food web drawn in (a) (i) on page 10: Primary consumer.
16. 2(a)(iii)c)1 markName the organism which performs EACH of the following functions in the food web drawn in (a) (i) on page 10: Secondary consumer.
17. 2(a)(iii)d)1 markName the organism which performs EACH of the following functions in the food web drawn in (a) (i) on page 10: Tertiary consumer (top carnivore).
18. 2(a)(iv)1 markFrom your food web in (a) (i), draw a food chain consisting of THREE organisms.
19. 2(a)(v)1 markWhat is the role of the organism to which the arrow points in a food chain?
20. 2(a)(vi)2 marksExplain why energy flows in one direction in the food chain.
21. 2(b)3 marksList THREE features of an environment which support living organisms.
22. 3(a)(i)1 markDefine EACH of the following terms: Stimulus.
23. 3(a)(ii)1 markDefine EACH of the following terms: Receptor.
24. 3(a)(iii)1 markDefine EACH of the following terms: Effector.
25. 3(b)(i)4 marksLabel EACH of the following parts of the eye on Figure 1: Pupil, Ciliary muscles, Retina, Optic nerve.
26. 3(b)(ii)1 markWhy is X called the 'blind spot'?
27. 3(c)3 marksA boy looks up from reading his book to see a helicopter flying in the distance. Account for the changes that would occur in the lens of both of his eyes to enable him to see the helicopter.
28. 3(d)3 marksWhich of the eyes in Figure 2, A or B, shows the appearance of an eye exposed to dim light? Explain your answer.
29. 3(e)1 markWhy is it important for the eye to respond when exposed to very bright light?
30. 4(a)6 marksIn the box below, draw a labelled diagram of the female reproductive system, and using an arrow, trace the path that a spermatozoon would have to take to fertilize an ovum.
31. 4(b)5 marksA young couple wants to choose between two contraceptive methods — barrier or surgical. Discuss why the male may prefer the barrier method rather than the surgical method of contraception. Your answer should include TWO…
32. 4(c)4 marksA biologist discovers that the flowers of a species of plants have no male reproductive parts. Suggest ONE method by which these plants produce offspring, and THREE advantages of this method.
33. 5(a)11 marksWith the aid of a chemical equation, explain what is meant by the term 'photosynthesis', and discuss how a dicotyledonous leaf is adapted to capture maximum sunlight and carbon dioxide for the process.
34. 5(b)4 marksOutline how decomposers assist in the cycling of carbon dioxide to make it available to green plants.
35. 6(a)4 marksState TWO causes of anaemia and describe TWO signs/symptoms of the disease.
36. 6(b)(i)2 marksState what is meant by EACH of the following terms: Homozygous, Heterozygous.
37. 6(b)(ii)6 marksWith the aid of a genetic diagram, show how a man and a woman who do NOT have sickle-cell anaemia can have a child who has the disease.
38. 6(b)(iii)3 marksExplain why the sickle-cell allele is more common in the population, in countries where the severe form of malaria is present.