Human Health and Disease Mock Test – Class 12 Biology

1. Match each example with the correct innate-immunity barrier category.

2. Which classification correctly groups the following structures?
P. Bone marrow
Q. Thymus
R. Spleen
S. Lymph nodes

3. Use the appearance described below. A person has dry, scaly, intensely itchy lesions that are especially troublesome in warm, moist body regions. Similar lesions may involve the nails or scalp. Which interpretation is most appropriate?

4. The principal functional distinction between primary and secondary lymphoid organs is that

5. An adolescent athlete misuses anabolic steroids for several months. Muscle bulk increases, but later imaging shows premature closure of the growth centres of long bones. Which consequence follows most directly from this developmental change?

6. A graph of drug use shows progressively increasing intake over several months while the desired effect remains roughly constant. At month six, intake suddenly falls to zero and withdrawal symptoms appear. Which two processes are demonstrated in sequence?

7. AIDS stands for

8. An adolescent begins drinking regularly at an early age but currently shows no severe liver disease. Why can the behaviour still represent an important long-term concern?

9. Which adverse-effect pattern is most consistent with anabolic-steroid abuse in males?

10. Which event represents an acute behavioural consequence associated with drug or alcohol abuse rather than a long-term organ complication?

11. A pregnant adolescent abuses alcohol and other drugs. Which two concerns are simultaneously supported biologically?

12. Four people use biologically active substances.
I. A postoperative patient receives morphine under medical supervision.
II. An athlete takes anabolic steroids without medical need to increase body bulk.
III. A patient takes a prescribed benzodiazepine exactly as directed.
IV. A person repeatedly takes a prescribed psychoactive medicine at excessive doses for non-medical effects.
Which cases most clearly represent abuse?

13. A graph shows helper T-lymphocyte abundance declining steadily during the progression of untreated HIV infection, while susceptibility to opportunistic infections increases. Which relationship best explains the two trends?

14. A person is exposed over time to tobacco-smoke carcinogens, while another cell acquires activation of a normal proto-oncogene. Which statement correctly relates these events to cancer biology?

15. Among the explicitly listed Plasmodium species, which inference is justified if the infection is identified as malignant malaria?

16. A person tests positive for HIV soon after infection but does not yet show the full clinical syndrome associated with advanced immunodeficiency. Which interpretation is best supported biologically?

17. Repeated drug use causes the receptors involved to become progressively less responsive, so the person needs increasingly larger amounts to obtain the same desired effect. This phenomenon is called

18. Ringworm incidence rises sharply during a hot, humid season among athletes who share towels. Which two factors most directly explain the increase?

19. A patient undergoes surgery to remove the main tumour, followed by additional radiotherapy and chemotherapy. Why can this combined approach be biologically reasonable?

20. A student refuses to sit beside or shake hands with a person living with HIV because the student believes ordinary physical contact will transmit the virus. Which correction is scientifically appropriate?

21. Substance abuse during pregnancy is especially concerning because

22. Study the following relationships.

Which interpretation is most appropriate?

23. During radiotherapy, treatment planning attempts to expose a tumour to lethal radiation while protecting surrounding normal tissues as much as possible. The main biological objective is to

24. An intestinal pathogen enters through contaminated food and must remain viable while passing through the acidic stomach before multiplying at a favourable site. Which biological requirement is most directly illustrated?

25. Which set contains only disorders or conditions specifically associated with smoking?

26. Consider the following disease-agent-site relations:
I. Typhoid — Salmonella typhi — small intestine
II. Pneumonia — Streptococcus pneumoniae — alveoli
III. Common cold — rhinoviruses — nose and respiratory passage
IV. Pneumonia — Haemophilus influenzae — large intestine
Which set contains only correctly matched relations?

27. A person initially uses a drug because of peer pressure, later develops tolerance and finally experiences withdrawal whenever intake stops. Which point in this progression provides the strongest evidence that physiological dependence has developed?

28. During allergy testing, small controlled amounts of three suspected allergens are tested separately. Only exposure to substance Q produces a clear allergic reaction. The most appropriate inference is that

29. Tumour cells in a patient remain poorly eliminated despite the presence of immune cells. Treatment with alpha-interferon is then added, and anti-tumour immune activity increases. Which interpretation is most appropriate?

30. A community programme combines removal of stagnant water, mosquito nets, wire mesh, insecticides and introduction of Gambusia into suitable water bodies. The common biological objective of these measures is to

31. A community reduces open faecal contamination of soil, washes vegetables thoroughly and improves drinking-water safety. Which infection should be particularly reduced through this combined intervention because infective eggs can contaminate soil, water and plant material?

32. Consider the following sequence associated with vaccination.
I. Exposure to antigenic material from the pathogen
II. Development of an acquired immune response
III. Formation of memory B and T cells
IV. Later encounter with the same pathogen
V. Rapid, intensified secondary response
Which sequence is biologically correct?

33. A person has a strong inherited predisposition to a particular cancer, but no tumour is currently visible. Another person has a suspicious tissue mass that is visible on imaging but requires confirmation of malignant cellular architecture. Which approaches best fit the two cases respectively?

34. Reverse transcription in HIV proceeds normally, producing viral DNA, but incorporation of that viral DNA into host-cell DNA is experimentally prevented. Which event would be most directly blocked?

35. An organism lives in or on a host and obtains benefit while causing harm to that host. In the context of human disease, this relationship most directly describes

36. Which sequence correctly represents a major route by which ascariasis can spread?

37. Which group consists of products associated with Cannabis sativa?

38. A person exposed to an allergen develops sneezing, watery eyes, a runny nose and difficulty in breathing. Which cellular event most directly explains these symptoms?

39. HIV is classified as a retrovirus. Which property of the virus is most directly linked with the need for reverse transcriptase?

40. The antibody class specifically associated with allergic responses is

41. Which objective is most consistent with the reason some performance-enhancing substances are misused in sports?

42. Which strategy is specifically recommended for reducing the likelihood that an adolescent begins using drugs merely because friends insist on it?

43. A student states, “Because ELISA is associated with AIDS, it must be a treatment that reduces HIV multiplication.” The most appropriate correction is that ELISA is

44. A graph shows that repeated use of a psychoactive drug is followed by progressively greater intake while the subjective effect remains approximately similar. Which process does the graph most strongly indicate?

45. A normal cell contains a proto-oncogene but does not show uncontrolled proliferation. Later, abnormal activation of that gene contributes to transformation. Which principle does this illustrate?

46. A treatment experimentally prevents malignant cells from entering the bloodstream but does not reduce the size of the original tumour. Which process would be most directly reduced?

47. A patient has sustained fever around to , weakness, stomach pain, constipation, headache and loss of appetite. If the condition becomes severe, which complication is specifically associated with the suspected disease?

48. Heroin is described primarily as a drug that

49. Consider the following statements about acquired immunity.
I. It shows specificity for particular pathogens or antigens.
II. It can remember a previous encounter with an antigen.
III. A subsequent encounter with the same antigen can produce an intensified response.
IV. It functions only through physical barriers such as skin.
Which combination is correct?

50. A person with dependence receives treatment that safely controls withdrawal symptoms but continues to strongly desire the psychological effects of the drug. Which problem may still remain?