CSEC Human and Social Biology · January 2010 · Paper 2

80 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 marksState ONE function of EACH of the following cell organelles: a) Cell membrane, b) Mitochondria.
2. 1(a)(ii)1 markWhich type of cells, muscle or skin cells, contain more mitochondria?
3. 1(b)1 markA friend classified a bacterium as a plant cell rather than an animal cell. Which cell organelle is present in BOTH a bacterium and a plant cell, but NOT in an animal cell?
4. 1(c)(i)1 markWhat is the causative agent of athlete's foot?
5. 1(c)(ii)2 marksSuggest ONE sign and ONE symptom of athlete's foot that Dennis may observe and experience.
6. 1(c)(iii)2 marksIdentify TWO bad personal hygiene practices which may have caused athlete's foot.
7. 1(c)(iv)1 markSuggest ONE treatment for athlete's foot.
8. 2(a)(i)3 marksComplete the word equation for photosynthesis: [blank] + [blank] --(light / chlorophyll)--> sugar + [blank].
9. 2(a)(ii)1 markIn what form, starch or glycogen, is sugar stored in plants?
10. 2(b)(i)2 marksIdentify ONE plant food rich in carbohydrates and ONE plant food rich in proteins.
11. 2(b)(ii)2 marksSuggest ONE way the human body uses carbohydrate and ONE way it uses protein.
12. 2(c)2 marksSuggest TWO ways by which human beings return carbon dioxide to the atmosphere.
13. 3(a)(i)2 marksName the parts labelled A and B in Figure 1.
14. 3(a)(ii)1 markState ONE function of the parts labelled B in Figure 1.
15. 3(b)(i)2 marksExplain what is meant by the term 'reflex action'.
16. 3(b)(ii)2 marksIdentify which of the two actions, throwing the ball or blinking, is a reflex action, and which is a voluntary action.
17. 3(c)(i)1 markComplete the diagram of the eye in Figure 2 to show where light from a near object will focus when Dinah looks at it.
18. 3(c)(ii)1 markSuggest the type of lens Dinah must use to correct long sightedness.
19. 3(c)(iii)1 markIn the box provided, draw the shape of the lens needed to correct short sightedness.
20. 4(a)3 marksName the blood vessels labelled A, B, and C in Figure 3.
21. 4(b)2 marksExplain why humans need a circulatory system to transport oxygen, while single-celled organisms like amoeba do not.
22. 4(c)4 marksExplain how an iron deficiency affects the transport of oxygen by red blood cells.
23. 4(d)1 markSuggest ONE sign or symptom which may result from a deficiency of iron.
24. 5(a)(i)2 marksUse a single square bracket ( [ ) on Figure 4 to label EACH of the following layers of the skin: a) D for the dermis, b) E for the epidermis.
25. 5(a)(ii)1 markIdentify the part labelled A in Figure 4.
26. 5(b)(i)2 marksExplain how Dwight's skin causes this flushed appearance.
27. 5(b)(ii)2 marksDwight goes to a closed room with a fan to cool down after the game. Why does he take a long time to cool down even though he is sweating?
28. 5(c)2 marksGive TWO examples of how the kidney maintains balance in the human body.
29. 5(d)1 markDwight drank a lot of water during the football game. Explain why this excess water did NOT pass out as urine.
30. 6(a)(i)1 markState the form of cell division involved in asexual reproduction.
31. 6(a)(ii)1 markState whether the genotype of offspring and parents is identical or different in asexual reproduction.
32. 6(a)(iii)1 markState which structure from the list (bulbs or pollen) is involved in asexual reproduction in plants.
33. 6(b)(i)2 marksName TWO instances when a medical abortion could be legally carried out.
34. 6(b)(ii)1 markSuggest ONE OTHER option that the School Counsellor could advise.
35. 6(c)4 marksExplain why tubal ligation is considered a reliable method of birth control while the rhythm method is NOT considered reliable.
36. 7(a)(i)1 markState the meaning of the term 'genetic variation'.
37. 7(a)(ii)1 markState the meaning of the term 'environmental variation'.
38. 7(b)1 markWhat is the name of the chemical which forms a gene?
39. 7(c)1 markSuggest ONE benefit of genetic variation.
40. 7(d)(i)4 marksComplete Figure 5 to show how sex (gender) is inherited in humans, showing parental genotypes, gametes, offspring genotypes, and offspring phenotypes.
41. 7(d)(ii)2 marksUse your answer to (d)(i) to explain why the number of males and females in a population is approximately the same.
42. 8(a)(i)1 markName the vector for dengue fever.
43. 8(a)(ii)1 markName the microorganism responsible for dengue fever.
44. 8(a)(iii)1 markWhat is the name of the form of dengue in which there is bleeding?
45. 8(b)(i)3 marksName THREE OTHER signs or symptoms that could confirm her suspicion.
46. 8(b)(ii)2 marksSuggest TWO recommended practices in treating dengue fever.
47. 8(c)2 marksLeptospirosis is caused by another vector, rats. Suggest TWO methods of controlling rats.
48. 9(a)(i)1 markWhat is 'AIDS'?
49. 9(a)(ii)2 marksName TWO methods of transmission of HIV, OTHER THAN sexual transmission.
50. 9(b)(i)2 marksOutline TWO effects of gonorrhoea on a developing foetus.
51. 9(b)(ii)2 marksOutline TWO ways in which babies become infected by mothers with HIV.
52. 9(c)(i)1 markSuggest ONE change in human behaviour which may have resulted in an increase in sexually transmitted infections.
53. 9(c)(ii)2 marksWrite TWO pieces of advice you would give to teenagers to prevent the spread of sexually transmitted infections.
54. 10(a)3 marksComplete Table 1 by identifying the missing origin of carbon dioxide (i), the pollutant from car exhaust toxic to the nervous system (ii), and an effect of sulphur dioxide (iii).
55. 10(b)5 marksDescribe TWO ways of purifying water using the materials shown in Figure 6.
56. 10(c)2 marksSuggest TWO water-borne diseases that can be contracted if bacteria are NOT removed from drinking water.
57. 11(a)(i)2 marksState TWO functions of water in the human body.
58. 11(a)(ii)3 marksName the vitamin which, when deficient, causes night blindness and identify TWO food sources of this vitamin.
59. 11(b)(i)11 marksExplain how Hansraj's body gets protein from the fish. Include a labelled diagram of the digestive tract, the stages in protein digestion, and the absorption of the end products.
60. 11(b)(ii)4 marksState whether Hansraj's meal is considered a balanced meal and give TWO reasons for your answer.
61. 12(a)(i)1 markWhat is 'testosterone'?
62. 12(a)(ii)2 marksState TWO functions of testosterone.
63. 12(a)(iii)2 marksIn which part of the male reproductive system are sperms made, and where are they stored?
64. 12(b)4 marksExplain how a prostate gland which is NOT functioning properly will affect fertilisation of an egg.
65. 12(c)4 marksIdentify TWO functions of the ovary and suggest how an ovary that is NOT functioning properly will affect reproductive processes in a female.
66. 12(d)(i)1 markIdentify the approximate date for ovulation from Figure 7.
67. 12(d)(ii)1 markIdentify the approximate date for possible fertilisation from Figure 7.
68. 12(d)(iii)1 markIdentify the approximate date for possible implantation of the fertilised egg from Figure 7.
69. 12(d)(iv)1 markIdentify the approximate date for menstruation from Figure 7.
70. 12(e)3 marksProvide THREE arguments which may be used in an educational programme to convince young people about the benefits of family planning.
71. 13(a)(i)3 marksIdentify the parts labelled A, B, and C in Figure 8.
72. 13(a)(ii)2 marksWhat is meant by the term 'vital capacity'?
73. 13(b)6 marksOutline the steps which should be taken immediately to resuscitate your friend.
74. 13(c)6 marksSuggest TWO factors, OTHER THAN illness, which may affect breathing rate, and explain how EACH factor causes an increase in blood carbon dioxide levels.
75. 13(d)3 marksIdentify ONE sign of tuberculosis and TWO ways by which the disease is spread.
76. 14(a)(i)3 marksDefine EACH of the following terms: Herbivore, Carnivore, Omnivore.
77. 14(a)(ii)2 marksWhat is meant by the term 'primary producer'?
78. 14(b)3 marksConstruct a food chain consisting of the following organisms: mountain chicken, cricket, humans, grass, and lizard.
79. 14(c)(i)6 marksDiscuss the adverse effects of insecticides on the environment, providing THREE distinct points.
80. 14(c)(ii)6 marksFarmers decide to use biological control using a wasp to kill citrus bugs. Suggest ONE advantage of this biological control method and TWO possible effects on the food chain.