Question

multiple choice question: microbiology

A) What contents are released by NK cells into infected cells to start the process of apoptosis? Antibodies. Granzymes. Viruses. T cell receptors.

B) The T cell receptor of CD4 T cell recognizes: Free peptides. MHC I / peptide complex. MHC II / peptide complex. Both a and c.

C) Th1 is a subset of CD4 T cell that are good for clearing: Viral infection. Extracellular bacterial infection. Intracellular bacterial infection. All of the above.

D) CD8 T cell are good for clearing: Viral infection. Extracellular bacterial infection. Intracellular bacterial infection. All of the above.

E) A capsule allows the bacteria to escape the host immune response by: Killing specific T cells. Activating the complement pathway. Prevent phagocytosis. Both a and c.

F) Fimbria on Uropathogenic E. coli is considered which mechanism of penetrating host defenses? Capsules. Cell wall components. Enzymes. Antigenic variations.

G) Hyaluronidase secreted by Streptococci function by: Clot formation. Degrading collagen. Degrading polysaccharide. All of the above.

h) Siderosphores allow bacteria to: Bind to iron. Compete with host for nutrient. Synthesize free iron. Both a and b.

i)Which part of LPS activates the innate immune response? O-antigen. Core sugars. Lipid A. All of the above.

j) Diphtheria toxin is a A-B toxin: True. False.

Answer 1

A)NK cell release granzymes to kill the infected cell and initiate apoptosis.NK cell release perforin.

B)MHC complex I is present on al the cell and is recognised by CD8+ T cell.MHC complex II is present on APC and is recognised by CD4+ Tcell.So the right answer is MHC/peptide II complex

C)Th1 is used for clearing the intracellular bacterial infection.Th2 for extracellular infection clearance.2)Extracellular infection.

D) CD8+ Tcell is used for the clearance of intracellular bacterial infection.Extracellular infection is removed by CD4+ T cell.So the right answer is intracellular infection.