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Infections by Listeria exhibit strict species-specifity because a) Cytoskeleton

ID: 35100 • Letter: I

Question

Infections by Listeria exhibit strict species-specifity because

a) Cytoskeleton polymerization involves different molecules in different species

b) Target cells have gained resistance in some species

c) Target receptors in different species are polymorphic at a single amino acid involved in bacterial adherence.

d) All of the above

Which of the following is the most likely target molecule exploited by a pathogen if neutrophils unable to kill the bacteria after phagocytosis.

a) Rho

b) Rac

c) Cdc42

d) Rab

e) All of the above

Listeria enters into host cells via endocytic vesicles formed through caveolin-independent mechanism.

a) True

b) False

If a bacterial toxin disables procaspase 9 and causes disruption of the protein in the target host cell, the cell cannot undergo programmed cell death even though it may receive external signals to do so.

a) True

b) False

Need explanations for your answers chosen. Thank you!

Explanation / Answer

Listeria uses E-cadherin as receptor in a species-specific manner. This cytoskeleton protein differs in different species. Hence, the correct option is (a) Cytoskeleton polymerization involves different molecules in different species.

Pathogens target all of the above proteins to avoid apoptosis. So, they can escape from being killed by the self-destruction of neutrophil.

Hence, the correct option is (e) all of the above.

Yes, listeria enters the host through caveolin-independent mechanism.

Hence, the correct option is True.

Yes, disruption of procaspase 9 would result in the inhibition of programed cell death.

Hence, the correct option is false.