CSEC Biology · January 2005 · Paper 2

39 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 marksComplete the key beside Figure 1b to indicate the colours represented by the blackened and non-blackened circles.
2. 1(b)(i)4 marksExplain why the colour of the drops remained the same for the 10 minutes in row A and row E.
3. 1(b)(ii)1 markWhat substance would you expect to find in Tube D after 2 minutes?
4. 1(b)(iii)2 marksDescribe the test that could be carried out to find out if you were correct at (b)(ii) above.
5. 1(c)(i)3 marksUsing information from the experiment in Figures 1a and 1b, complete the graph below to show the effect of temperature on the time taken for the reaction between the starch and the enzyme to be completed.
6. 1(c)(ii)1 markAt what temperature did the reaction take place most rapidly?
7. 1(c)(iii)4 marksWhat would you expect to happen if, at the end of the 10-minute period, the contents of Tubes A and E were brought to 30°C and then tested with iodine? Give ONE reason for your answer in EACH case.
8. 1(d)(i)5 marksUse the information on page 2 to describe the procedure used to set up this investigation, by placing each step in the correct order in which it should be carried out to ensure accuracy. Include ONE precaution that you…
9. 1(d)(ii)1 markExplain the importance of stirring the mixture.
10. 1(e)(i)1 markHow should the cotyledons be prepared for testing?
11. 1(e)(ii)3 marksExplain what happens to the starch stored in the cotyledons when the seed germinates.
12. 1(f)(i)2 marksExplain the appearance of the seedlings in Figure 1c.
13. 1(f)(ii)1 markIf you are asked to set up an investigation in a laboratory to show that your explanation in (f)(i) is correct and all you have is an old shoe box, how would you prepare the box for the investigation?
14. 2(a)(i)4 marksLabel the structures involved in breathing in Figure 2a above.
15. 2(a)(ii)1 markAdd a line to Figure 2a to show the position of the diaphragm when breathing in.
16. 2(a)(iii)1 markState what is happening to the rib cage at the same time that the diaphragm is moving to the position you have shown in (a)(ii).
17. 2(b)(i)1 markIndicate with an 'X' on Figure 2a, where the structures shown in Figure 2b are found.
18. 2(b)(ii)2 marksName the TWO major blood vessels that branch to form the capillaries shown in Figure 2b.
19. 2(b)(iii)3 marksExplain how oxygen from the air in the lungs moves to the rest of the body and into cells where it is needed.
20. 2(c)(i)3 marksWhy are breathing and respiration BOTH important to mammals?
21. 2(c)(ii)2 marksSuggest ONE reason why plants do not need to breathe although respiration is important to them also.
22. 3(a)4 marksUsing ALL the available data, describe the changes in carbon dioxide concentration shown in Figure 3.
23. 3(b)(i)2 marksIdentify the TWO plant processes that affect the amount of carbon dioxide in the atmosphere.
24. 3(b)(ii)2 marksExplain the changes taking place in the carbon dioxide concentration over the forest between 4.00 a.m. and 4.00 p.m.
25. 3(c)(i)1 markWhat environmental factor was MAINLY responsible for the changes which were seen in the graph in Figure 3?
26. 3(c)(ii)4 marksExplain how the factor you named at (c)(i) was responsible for the changes observed over the 24-hour period.
27. 3(d)3 marksGive THREE biological reasons why forests are important.
28. 4(a)4 marksIdentify the structures labelled A to D in Figure 4.
29. 4(b)3 marksState the functions of Structures A and D in Figure 4.
30. 4(c)2 marksState TWO ways in which the cell shown in Figure 4 is different from a human white blood cell.
31. 4(d)(i)2 marksHow many chromosomes would be present if the cell were part of a petal?
32. 4(d)(ii)2 marksHow many chromosomes would be present if the cell were part of a pollen grain?
33. 4(e)2 marksThe concentration of sugars in the cell sap has been calculated to be 10%. Describe what will happen to the cell if it is placed in a 50% sugar solution.
34. 5(a)(i)2 marksWhat does the term 'homozygous' mean?
35. 5(a)(ii)5 marksComplete the genetic diagram below to show what happened the first time the two varieties were crossed, if small flowers are dominant to large flowers.
36. 5(a)(iii)1 markWhy would the breeding programme have to continue for many generations?
37. 5(b)(i)2 marksWhat is the advantage to a plant of having large flowers and large leaves?
38. 5(b)(ii)2 marksWhat might be the advantage to the flower farmer of having a variety with BOTH large flowers and large leaves?
39. 5(b)(iii)2 marksGive ONE other characteristic of the new flower variety that the flower farmer would want and say why it would be important to the farmer.