CSEC Biology · May/June 2017 · Paper 2

32 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)2 marksWrite a suitable aim for this experiment.
2. 1(a)(ii)2 marksIn which of the tubes, A or B, would germination most likely occur? Give ONE reason for your answer.
3. 1(a)(iii)2 marksState TWO roles that the moisture from the cotton wool plays in the process of germination.
4. 1(b)(i)1 markWhat type of movement is shown by the plants in Figure 2?
5. 1(b)(ii)2 marksState a hypothesis that the students could test by using the apparatus and materials shown in Figure 2.
6. 1(b)(iii)1 markThe students want the seedlings to grow straight towards the ceiling. Suggest how they could manipulate the apparatus to get this result.
7. 1(b)(iv)4 marksThe seedlings shown in Figure 2 use all the nutrients stored in the cotyledons. Discuss the process by which these plants can make more nutrients.
8. 1(b)(v)4 marksDiscuss the processes by which the raw materials required for making nutrients reach the leaves of the plant.
9. 1(c)(i)4 marksStarch is the most common carbohydrate that is found in the leaves of green plants. Describe a test that the students could do in the laboratory to investigate whether starch is present in the leaves of the seedlings.
10. 1(c)(ii)1 markName ONE plant organ, other than leaves, where starch may be found.
11. 1(c)(iii)2 marksInstead of starch, animals store complex carbohydrates such as glycogen. Name TWO organs in an animal's body which store glycogen.
12. 2(a)5 marksComplete the classification by writing the correct answers at (i), (ii), (iii), (iv) and (v) in Figure 3.
13. 2(b)(i)2 marksDefine the term 'species'.
14. 2(b)(ii)2 marksUsing the human species as an example, explain why physical appearance or morphology is NOT always useful for identifying organisms belonging to the same species.
15. 2(b)(iii)2 marksSuggest ONE reason why biologists use the biological concept of species instead of physical characteristics to classify organisms.
16. 2(c)(i)2 marksUsing the biological concept of a species, state TWO reasons why they were reclassified.
17. 2(c)(ii)2 marksThe new species of lizards living in the mountainous region of the island were found to be smaller than those living on the lowlands. Suggest TWO reasons for this variation.
18. 3(a)(i)3 marksIdentify Hormones X and Y and the event occurring at Z.
19. 3(a)(ii)2 marksWhat is the role of EACH hormone in the menstrual cycle?
20. 3(a)(iii)2 marksName the organ that produces Hormones X and Y.
21. 3(a)(iv)4 marksDiscuss the fate of the following structures shown in Figure 4 if fertilization of the ovum occurs: Corpus luteum, Uterus lining.
22. 3(b)1 markSome contraceptive pills contain hormones. Suggest how this may prevent pregnancy.
23. 3(c)3 marksA drug company is developing a male contraceptive pill. Suggest THREE ways in which this could prevent pregnancy.
24. 4(a)(i)4 marksExplain how structures in the human eye control the amount of light that enters the eye.
25. 4(a)(ii)5 marksJenny enters a dimly lit room and cannot see the colours of the furniture until the lights are switched on. Explain how Jenny is able to discern objects in the dimly lit room but cannot see the colours until the lights…
26. 4(b)6 marksA certain form of colour-blindness is inherited as a recessive allele carried on the X chromosome. It is thus said to be 'X-linked' or 'sex-linked'. A woman with normal colour vision, whose father is colour-blind, mates…
27. 5(a)6 marksDescribe the chemical digestion of carbohydrates, fats and proteins from the mouth until they are absorbed in the small intestines.
28. 5(b)(i)4 marksDescribe how the body systems work together to assimilate glucose molecules.
29. 5(b)(ii)5 marksExplain how the assimilation of glucose by a non-diabetic person differs from that of a person suffering from diabetes.
30. 6(a)6 marksUsing a suitable example of EACH, distinguish between a predator-prey relationship and parasitism.
31. 6(b)(i)6 marksOutline THREE advantages and THREE disadvantages of this method of biological control compared to the use of chemicals.
32. 6(b)(ii)3 marksExplain how biological control may contribute to biological evolution through natural selection in an ecosystem.