15. Which of the following proteins would not need localization signal?
A.A nuclear protein
B.A cytosolic protein
C.A protein bound to the endoplasmic reticulum (ER) membrane
D.A cell surface protein

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16. Following are the defenses of the colon except
A.sIgA
B.fast flow rate
C.dense resident microbiota
D.mucus

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17.  Natural killer cells are involved in
A.tumour rejection
B.allograft rejection
C.non-specific killing of virus transformed target cells
D.all of these

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18. Which of the following(s) is/are the determinants of antigenicity?
A.Chemical nature
B.Size of the antigen
C.Foreignness
D.All of these

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19. Which of the following is correct?
A.All T Cells are CD4+
B.An epitope can have multiple antigens
C.T Cell receptors are generated by random assortment of gene cassettes
D.MHC Class II molecules are generated by random assortment of gene cassettes

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20. Immunity is not long lasting to
A.influenza
B.whooping cough
C.diphtheria
D.mumps

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21. Lysozyme is present in
A.sweat
B.Cerebro spinal fluid (CSF)
C.urine
D.saliva

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