Practice Questions

1. Practice Questions True or False

2. The antibody-mediated class of hypersensitivies primarily involves IgE False – IgE is in immediate hypersensitivity; IgG and IgM are in antibody-mediated hypersensitivity

3. Contact dermatitis is an example of cell-mediated hypersensitivity True

4. The sensitisation phase of immediate hypersensitivity involves activation of Th2 cells, IgE class-switching, production of IgE and binding of IgE to Fc receptors on mast cells True

5. Immediate hypersensitivity reactions have both an immediate and a late phase True

6. Only exogenous antigens can cause immune complex-mediated hypersensitivity False – both endogenous and exogenous antigens can

7. Activation of mast cells anywhere within the body will produce the same allergic response False – it depends on where the mast cell is (eg. circulatory Vs respiratory Vs skin)

8. Anaphylactic shock is due to pump failure False – anaphylactic shock is a type of distributive shock (not cardiogenic)

9. Corticosteroids can be used as treatment for asthma and eczema False – glucocorticoids are used

10. Antihistamines selectively inhibit the H1 receptor True

11. Deep partial thickness burns are commonly painful, thus requiring strong pain relief. False – they are painless

12. Full thickness burns involve burns to the muscle underlying the subcutaneous tissue False – This burn only reaches the subcutaneous tissue

13. Superficial burns do not cause scarring True

14. The Parkland formula is used to determine the volume of colloid needed for fluid resuscitation in burns patients. False – Parkland formula is used for crystalloids, Muir/Barclay formula is used for colloids

15. ANZBA guidelines stipulate that full thickness burns >10%TBSA should be referred to a burns unit False – full thickness: >5% but other burns are >10%

16. The first step in wound healing is inflammation False – it is haemostasis then inflammation

17. Healing by second intention results in the formation of more granulation tissue and a larger fibrin clot than healing by first intention does True

18. An autograft is a graft between sites on the same person True

19. Systemic inflammatory response syndrome is also known as the acute-phase response True

20. The major manifestations of SIRS is a decreased HR, decreased BP, increased RR and increased partial pressure of CO2 False: increased HR, decreased BP, increased RR and decreased partial pressure of CO2

21. The defining feature of severe sepsis is that it does not respond to fluid therapy False – Septic shock does not respond to fluid therapy

22. Health-care associated infections and hospital-acquired infections are the same False

23. First-line antibiotic choice is based on pathogen-directed therapy False – it is based on empiric therapy (aetiology is unknown)

24. Tetracyclines bind the 30S ribosomal subunit to prevent protein synthesis True

25. Trimethoprim is a dihydrofolatereductase inhibitor True

26. The vascular layer of the eyeball includes the choroid, ciliary body and iris True

27. The superior rectus muscle caused elevation, adduction and medial rotation of the eye True

28. The superior oblique is innervated by the abducens nerve False – it is innervated by the trochlear nerve

29. The ophthalmic artery supplies the orbit True

30. Accommodation is controlled by the ciliary muscles True

31. Rods (photoreceptor cells) are concentrated at the fovea False – concentrated at the periphery of the retina (cones are concentrated at the fovea)

32. The corneal reflex involves afferent facial nerve fibres and efferent trigeminal nerve fibres False – afferent trigeminal and efferent facial

33. Cataracts are growths of tissue on the sclera that may extend onto the cornea False – cataract = clouding of the lens; pterygium = growth of tissue on the sclera that may extend onto the cornea

34. Freckles are a skin lesion which involve an increase in the number of pigment cells False – they involve increased pigment, but without an increase in the number of pigment cells

35. Adnexal tumours are benign epithelial tumours True

36. Actinic keratosis are dysplastic lesions which can become SCCs True

37. The growth phases of a malignant melanoma are (in correct order): lentigenousmelanocytic hyperplasia; lentigenousjunctional naevus; lentigenous compound naevus; early melanoma; advanced melanoma True

38. Lentigomaligna melanoma usually occur on the chest False – they usually occur on the face of elderly patients

39. Clark level II involves invasion of the reticular dermis False – papillary dermis only

40. BCCs arise due to high-intensity sun exposure False – they are due to chronic sun exposure

41. SCCs can be either in situ or invasive True

42. It is a legal requirement for doctors to report on any patient’s lack of fitness to drive False

43. In adults, red marrow is found in the appendicular skeleton False – it is found in the axial skeleton

44. Aplastic anaemia causes microcytic anaemia False – it causes normocytic anaemia

45. In iron deficiency, MCV is decreased True

46. Iron is stored attached to cytochrome B False – iron is stored as ferritin. Cytochrome B reduces Fe3+ to Fe2+ at the brush border

47. Hepcidin inhibits ferroportin on enterocytes True

48. Intrinsic factor is secreted by chief cells in the gastric fundus False - it is secreted by parietal cells

49. Megaloblastic anaemia is commonly treated by blood transfusion. False – it is generally treated by B12 supplementation, folate therapy and/or treatment of the underlying condition

50. There can be both immediate and delayed haemolytic transfusion reactions True