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1. An adequate intake of vitamins B9 (folic acid) and B12 is important for health because they are required for: (a) maintenance of DNA synthesis and repair (b) synthesis and export of lipids (c) the unfolded protein response (d) detoxification of reactive oxygen species (e) glycation of proteins2. ...

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1. An adequate intake of vitamins B9 (folic acid) and B12 is important for health because they are required for: (a) maintenance of DNA synthesis and repair (b) synthesis and export of lipids (c) the unfolded protein response (d) detoxification of reactive oxygen species (e) glycation of proteins

2. The enzyme known as catalase is important in: (a) the repair of DNA breaks (b) protection against oxidants (c) degradation of extracellular matrix proteins (d) generating energy for cell metabolism (e) helping damaged proteins to re-nature

3. Acute intracellular oedema is found in cells that: (a) are undergoing apoptotic cell death (b) have died from massive trauma (c) have reduced control of sodium ion movement (d) are storing large amounts of carbohydrates, lipids or abnormal proteins

4. Adaptive responses to cell stress include the responses to DNA damage, oxidant stress, heat shock, hypoxia, and endoplasmic stress. A feature common to all of these is: (a) the activation of the p53 molecule (b) cell swelling, membrane permeability and lysis (c) an insufficiency of glucose with loss of ATP synthesis (d) an increase in the activity of glucose transporters and glycolytic enzymes (e) the induction of gene transcription

5. A form of cell death that involves activation of inflammasomes and of caspase 1, followed by cell lysis is: (a) necrosis

(b) oncosis (c) necroptosis (d) pyroptosis (e) autophagic cell death

6. Apoptosis will generate inflammation under conditions in which: (a) it is triggered by death receptors such as Fas (b) it is triggered by detachment from the extracellular matrix in a process called anoikis (c) apoptotic bodies are released (d) apoptotic bodies cannot be phagocytosed by neighbouring cells (e) cytochrome C is released from mitochondria

7. In the presence of signals such as histamine and tryptases, arterioles contribute to the development of the cardinal signs of inflammation when: (a) they undergo dilatation (b) they are denuded of endothelial cells (c) cells comprising their endothelial lining retract to become leaky (d) their endothelial cells become adherent for neutrophils (e) they are occluded by thrombus

8. A lipid-derived signalling molecule that induces platelet aggregation and vasoconstriction, and so contributes to haemostasis, is: (a) thromboxane A2 (b) prostaglandin E2 (c) phosphatidylcholine (d) phosphatidylserine (e) any leukotriene

9. The key protease in the fibrinolytic pathway is: (a) thrombin (b) plasmin

(c) esterase (d) kallikrein (e) caspase 1

10. The functions of C3a and C5a include: (a) vasopermeability and neutrophil attraction (b) digestion of extracellular matrix (c) the removal of fibrin aggregates (d) the direct killing of bacteria (e) platelet disaggregation and vasodilatation

11. Suppuration may be induced by neutrophil-derived hydrolytic enzymes and is characteristic of: (a) coagulative necrosis (b) ischaemic injury (c) diapedesis (d) fat necrosis (e) cellulitis and abscesses

12. In sterile inflammation, N-formylated peptides act as strong chemotactic signals and are derived from: (a) degraded extracellular matrix (b) chromatin (c) the granules of phagocytes (d) mitochondria (e) advanced glycation end products

13. Multiorgan failure is a lethal condition that may be seen in: (a) the acute phase response (b) systemic inflammatory response syndrome (c) leukocytosis

(d) TH1-mediated chronic inflammation (e) the coagulation cascade

14. During wound healing, the process of debridement typically occurs during: (a) haemostasis (b) the inflammatory phase (c) the proliferative phase (d) re-epithelialisation (e) remodelling

15. The cells responsible for the contraction of wounds are: (a) macrophages (b) fibroblasts (c) myofibroblasts (d) migrating epithelial cells (e) smooth muscle cells

16. During wound healing, regeneration involves: (a) the formation of granulation tissue (b) scarring with a protracted period of tissue remodelling (c) proliferation of terminally differentiated cells (d) replacement of lost tissue by cells of the same kind (e) repair of tissue that has lost both epithelial and stromal components

17. Fibrin is an insoluble protein that is: (a) produced by fibroblasts (b) responsible for the bulk of scar tissue (c) present in clots and thrombi (d) a major constituent of basement membranes (e) responsible for the strength of normal skin

18. Metaplasia arises during the progression of Barrett’s oesophagus, and is that condition in which: (a) stomach contents are regurgitated into the lower oesophagus (b) stomach acid induces inflammation (c) squamous epithelium is replaced by intestinal epithelium (d) bile acids cause injury to epithelial cells (e) N-nitroso compounds damage DNA and contribute to cancer development

19. Every person has a level of background inflammation that may be increased by: (a) physical exercise (b) lifestyles that increase the ratio of symbionts to pathobionts (c) diets that generate abundant short chain fatty acids in the colon (d) dietary omega-3 fatty acids that stimulate GPR120 receptors (e) obesity

20. The evidence that Crohn’s disease has a significant environmental component comes from the observation that: (a) the CARD15 gene is mutated mainly in Caucasians (b) the incidence has risen sharply in industrialised countries in 40 years (c) the immune system is over-activated (d) it appears in adolescence or later (e) it occurs throughout the digestive tract but especially at the end of the ileum

21. A liver condition, associated with abnormalities in metabolism, in which there is cell damage, inflammation and sometimes fibrosis is known as: (a) non-alcoholic steatohepatitis (b) steatosis (c) cirrhosis (d) end-stage liver disease (e) liver failure

22. Lipotoxicity in the liver is considered to arise from elevated concentrations of: (a) cholesterol (b) free fatty acids (c) triglycerides (d) phospholipids (e) very low density lipoprotein

23. During infection with Mycobacterium tuberculosis, the change that allows infection of other individuals typically is: (a) formation of caseous necrosis (b) formation of a fibrous capsule (c) liquefaction resulting in cavitation (d) formation of a granuloma (e) development of TH1 cell-mediated immunity

24. The inability to distinguish between self-cells and nonself-cells may lead to: (a) hypersensitivity (b) auto-immune disease (c) immunodeficiency (d) tolerance (e) all of the above

25. Autoimmune disease can be triggered by cross-reactivity with a pathogenic antigen by the process of: (a) immune deficiency (b) anergy (c) molecular mimicry (d) hypersensitivity (e) antigen presentation

26. Which of the following factors is/are known to predispose people to the development of systemic lupus erythematosus (SLE)? (a) The presence of HLA-D2, HLA-D3 and HLA-D8 risk alleles (b) A single nucleotide polymorphism in the PTPN22 gene (c) Exposure to sunlight (d) Female gender (e) All of the above

27. All hypersensitivities involve two stages. These are known as the: (a) sensitisation and effector stages (b) initiation and resolution stages (c) sensitisation and resolution stages (d) initiation and effector stages (e) initiation and sensitisation stages

28. Another term for type I hypersensitivity is: (a) direct antibody-mediated cytotoxic hypersensitivity (b) IgE-mediated hypersensitivity (c) delayed type hypersensitivity (d) immune complex-mediated hypersensitivity (e) IgG-mediated hypersensitivity

29. During type I hypersensitivity, mast cells become sensitised by: (a) phagocytosis of allergen by mast cells (b) dendritic cells that express IL-4 (c) degranulating dendritic cells (d) IgE binding to FcεRs located on mast cells (e) dendritic cells that express IL-4, IL-5 and IL-13

30. What is the major characteristic of staphylococcal food poisoning? (a) It is caused by protease and heat-sensitive toxins

(b) It results from infection with Staphylococcus aureus (c) Disease symptoms start about 7 days after ingestion of toxins (d) Patients recover after 1-2 days (e) It can be prevented by vaccination

31. Cholera toxin causes watery diarrhoea by: (a) lysing enterocytes in the gut epithelium by pore formation (b) decreasing the intracellular cAMP concentration (c) inducing an apoptotic signal in the host cell (d) causing inflammation of the gut epithelium (e) deregulation of the cystic fibrosis transmembrane conductance regulator (CFTR)

32. Staphylococcus aureus beta-toxin damages host cell membranes by which mechanism? (a) Phospholipase A activity (b) Phospholipase C activity (c) Serine-protease activity (d) Metalloprotease activity (e) Formation of pores into lipid membranes

33. Which of the following statements about acute rheumatic fever (ARF) is CORRECT? (a) ARF is characterized by a type II hypersensitivity reaction (b) ARF is an infectious disease with group A streptococcus (c) ARF is an inflammation caused by the release of endotoxin by the bacteria (d) Stimulation of Toll-like receptor 4 plays a major role (e) Secreted bacterial toxins contribute to inflammation

34. Which of the following is an important cytokine involved in inflammation damage? (a) Interleukin 4 (IL-4) (b) Interleukin 10 (IL-10) (c) Tumour necrosis factor-α (TNF-α)

(d) Endotoxin (e) Lipopolysaccharide (LPS)

35. Superantigens produced by Staphylococcus aureus cause which of the following effects? (a) Haemolysis (destruction of red blood cells) (b) Strong activation of a pro-inflammatory cytokine response (c) Strong activation of an anti-inflammatory cytokine response (d) Induction of apoptosis in host epithelial cells (e) Rapid spreading of bacteria through host tissue

36. Which of the following methods makes use of a dideoxynucleotide (ddNTP)? (a) Sanger Sequencing (b) Western blotting (c) Microarrays (d) FISH (e) PCR

37. During PCR, the denaturation step typically occurs at which of the following temperatures? (a) 30-35 C (b) 50-65 C (c) 72 C (d) 90-95 C (e) 4 C

38. TaqMan probes are routinely used in which of the following methods? (a) Standard PCR (b) Real-time PCR (c) Microarrays (d) FISH (e) Next generation sequencing

39. Which of the following is an example of a transition mutation? (a) C>T (b) C>G (c) T>A (d) T>G (e) C>A

40. The following symbol,

, if present in a pedigree, represents which of

following features? (a) Miscarriage (b) Consanguinity (c) Male proband (d) Stillbirth (e) Deceased individual

41. Myotonic dystrophy normally shows which of the following patterns of inheritance? (a) X-linked recessive (b) Autosomal recessive (c) Y-linked (d) X-linked dominant (e) Autosomal dominant

42. Which of the following tests is undertaken at the latest stage? (a) Pre-implantation genetic diagnosis (b) Amniocentesis (c) Post-natal testing (d) Chorionic villus sampling (e) Pre-implantation genetic screening

43. Which of the following conditions exhibits extensive locus heterogeneity?

(a) Huntington’s disease (b) Cystic fibrosis (c) Trisomy 21 (d) Duchenne muscular dystrophy (e) Retinitis pigmentosa

44. A couple, both with autosomal recessive congenital deafness, have three children. All children have normal hearing. A feature of this pedigree would be: (a) incomplete penetrance (b) allelic heterogeneity (c) anticipation (d) locus heterogeneity (e) variable expressivity

45. Which of the following bacterial pathogens colonises its host using teichoic acid as a non-specific adhesin? (a) Mycobacterium tuberculosis (b) Neisseria meningitidis (c) Pseudomonas aeruginosa (d) Staphylococcus aureus (e) Bacillus anthracis

46. Which of the following bacterial pathogens can evade clearance by the host immune response by hiding inside macrophages? (a) Mycobacterium tuberculosis (b) Neisseria meningitidis (c) Pseudomonas aeruginosa (d) Staphylococcus aureus (e) Bacillus anthracis

47. Which of the following bacterial pathogens can evade killing by complement using a

sialic acid capsule? (a) Streptococcus pyogenes (b) Neisseria meningitidis (c) Pseudomonas aeruginosa (d) Staphylococcus aureus (e) Bacillus anthracis

48. Loss of function of the somatostatin-secreting cells after an infection with Helicobacter pylori will most likely lead to: (a) gastric cancer (b) gastric ulcer (c) diarrhoea (d) duodenal ulcer (e) duodenal cancer

49. Angiogenesis may be defined as the: (a) proliferation of stem cells (b) differentiation of transit-amplifying cells (c) development of antibody-producing cells (d) invasion of fibroblasts into wounds (e) formation of new blood vessels

50. Helicobacter pylori attaches to the sialated Lewis X (SLex) receptor on the host cell using which adhesin? (a) CagA (b) SabA (c) VacA (d) Protein A (e) Teichoic acid...