CSEC Biology · May/June 2021 · Paper 2

36 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)4 marksName the two raw materials and state the two conditions necessary for photosynthesis.
2. 1(b)(i)3 marksOn the grid provided on page 5, make a drawing of the leaf that is twice the size of Figure 1.
3. 1(b)(ii)3 marksOn the drawing made on page 5, label each of the specified parts: apex, lamina, midrib, petiole.
4. 1(c)(i)1 markSuggest one way in which the leaf is adapted for gaseous exchange.
5. 1(c)(ii)1 markSuggest one way in which the leaf is adapted for preventing excess water loss.
6. 1(d)3 marksSuggest three reasons why there is still a need for green plants to store food even though they produce food by photosynthesis.
7. 1(e)3 marksSuggest three reasons why glucose, the initial carbohydrate product of photosynthesis, is not stored in green leaves.
8. 1(f)3 marksDescribe the test that could be used to determine if a green leaf has stored starch.
9. 1(g)4 marksExplain two ways in which the human digestive system is adapted for the mechanical digestion of food.
10. 2(a)2 marksDefine the term 'pollination'.
11. 2(b)2 marksDescribe how male gametes reach female gametes in humans.
12. 2(c)3 marksLabel each of the following parts on the diagram: stigma, style, ovary and ovule.
13. 2(d)4 marksExplain why a human embryo does not have large nutrient stores but a plant embryo does.
14. 2(e)4 marksSuggest four reasons why a couple would be advised to use the permanent method of birth control for the male rather than the permanent method for the female.
15. 3(a)(i)1 markIdentify a producer from the food web.
16. 3(a)(ii)1 markIdentify a predator from the food web.
17. 3(a)(iii)1 markIdentify a primary consumer from the food web.
18. 3(b)2 marksState two roles of the producer in the food web.
19. 3(c)(i)1 markIdentify one biotic factor that would affect the organisms shown in Figure 3.
20. 3(c)(ii)1 markIdentify one abiotic factor that would affect the organisms shown in Figure 3.
21. 3(d)(i)2 marksExplain why there are fewer organisms at the top than at the bottom of the food web.
22. 3(d)(ii)4 marksDiscuss two possible consequences of the hawk becoming extinct in the ecosystem shown in Figure 3.
23. 3(e)2 marksSuggest two reasons why decomposers are important organisms in all food webs.
24. 4(a)6 marksUse Figure 4 to describe how urine is formed.
25. 4(b)(i)4 marksExplain why there is a high concentration of glucose in the urine of a diabetic patient.
26. 4(b)(ii)3 marksState one similarity and two differences between the method by which the human body regulates blood sugar levels and the method by which it regulates the amount of water in the blood.
27. 4(c)2 marksSuggest two ways in which kidney damage can be prevented in diabetic and hypertensive patients.
28. 5(a)6 marksUse clearly labelled diagrams to illustrate the structure of a red blood cell and the structure of a white blood cell.
29. 5(b)4 marksExplain how any two features of a red blood cell ensure that it is suitable for its major function in the human body.
30. 5(c)5 marksWith the aid of a genetic diagram, explain how an individual may have a blood type that is different from either parent.
31. 6(a)2 marksOutline Darwin's theory of natural selection.
32. 6(b)2 marksExplain why the development of antibiotic resistance by bacteria is considered to be an example of natural selection.
33. 6(c)2 marksA farmer wishes to use artificial selection to alter the characteristics of his crops. Suggest two ways in which artificial selection will benefit the farmer.
34. 6(d)(i)3 marksSuggest three possible reasons for the increase in tail length observed in these iguanas.
35. 6(d)(ii)2 marksProvide an explanation to support the conclusion that the iguanas with longer tails were not a new species.
36. 6(e)4 marksDescribe two situations which may lead to the evolution of a new species.