CSEC Biology · January 2021 · Paper 2

40 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)2 marksState TWO reasons why enzymes are referred to as 'biological catalysts'.
2. 1(b)(i)4 marksRecord the results presented on the graph in Figure 1 in a suitable table.
3. 1(b)(ii)4 marksWith reference to the rate of enzyme activity, suggest TWO reasons for the shape of the graph during EACH of the following pH ranges: pH 4-5 and pH 6-8.
4. 1(b)(iii)1 markSuggest ONE reason why the graph has a 'U' shape.
5. 1(b)(iv)1 markPredict how many seconds it would take for amylase to completely break down starch at pH 5.5 using the graph in Figure 1.
6. 1(b)(v)1 markDetermine the optimum pH of amylase using the graph in Figure 1.
7. 1(b)(vi)1 markPredict the pH at which amylase would completely break down starch in 80 seconds.
8. 1(c)5 marksWith reference to Figure 1 on page 4, describe a suitable procedure that can be used to investigate the effect of pH on the time taken for amylase to digest starch.
9. 1(d)2 marksSuggest TWO ways in which mammals can decrease the time they take to break down food molecules if the food molecule is too large.
10. 1(e)2 marksComplete Table 1 by identifying the deficiency disease associated with Vitamin C and the vitamin/mineral deficient when there is abnormal clotting of the blood.
11. 1(f)(i)1 markExplain ONE way in which white blood cells defend the body against disease.
12. 1(f)(ii)1 markExplain ONE way in which platelets defend the body against disease.
13. 2(a)(i)4 marksName the structures labelled A, B, C and D on Figure 2.
14. 2(a)(ii)1 markSuggest ONE way in which photosynthesis would be affected if ALL of the air spaces in the leaf of the flowering plant were filled with cells.
15. 2(b)3 marksList THREE ways in which the leaf of a plant is adapted for photosynthesis.
16. 2(c)(i)1 markState if there is any difference between the function of plant chromosomes and the function of animal chromosomes.
17. 2(c)(ii)1 markState ONE reason for your answer in (c)(i).
18. 2(d)(i)1 markDescribe the region of the line of the graph labelled A in Figure 3.
19. 2(d)(ii)1 markUse the principles of photosynthesis to suggest ONE reason for the shape of the graph in the region A.
20. 2(d)(iii)1 markDescribe the region of the line of the graph labelled A-B in Figure 3.
21. 2(e)2 marksDespite the increase in the global concentrations of atmospheric carbon dioxide, there is no corresponding increase in the rate of photosynthesis in flowering plants. Suggest ONE reason for this observation.
22. 3(a)4 marksList FOUR structures that are common to both plant and animal cells.
23. 3(b)(i)1 markDefine the term 'diffusion'.
24. 3(b)(ii)1 markDefine the term 'osmosis'.
25. 3(b)(iii)1 markDefine the term 'active transport'.
26. 3(c)(i)1 markState the expected result of the experiment investigating the effect of concentration on diffusion shown in Figure 4.
27. 3(c)(ii)3 marksExplain the expected results stated in your answer in (c)(i).
28. 3(d)4 marksDiscuss FOUR ways in which diffusion is important to mammals.
29. 4(a)6 marksSequentially describe the process of mitosis.
30. 4(b)3 marksState TWO advantages and ONE disadvantage of animal cloning.
31. 4(c)6 marksExplain THREE other ways in which the process of mitosis is important for organisms besides animal cloning.
32. 5(a)3 marksList the THREE types of symbiotic relationships.
33. 5(b)3 marksComplete Table 2 by stating the type of symbiotic relationship that exists in each described scenario.
34. 5(c)6 marksExplain any THREE social, economic or environmental implications that the spread of the 'bird flu' infection may have on Mr Brown's livestock and vegetables.
35. 5(d)3 marksList THREE other reasons why animals on a farm should be allowed to move from place to place.
36. 6(a)(i)3 marksName THREE valves found in the heart.
37. 6(a)(ii)3 marksOn Figure 5, label the THREE valves named in (a)(i) to show their location.
38. 6(b)1 markState ONE difficulty that Joy may experience as a result of having an abnormal heart valve.
39. 6(c)2 marksOutline how the cause of diabetes is different from the cause of hypertension.
40. 6(d)6 marksCompare the methods used to manage diabetes and hypertension by outlining TWO similarities and TWO differences in these methods.