50. Which of the following viruses belong to family Hepadnaviridae?
A.Hepatitis A virus
B.Hepatitis B virus
C.Hepatitis D virus
D.All of these

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51. Inclusion bodies of measles virus are
A.intracytoplasmic
B.intranuclear
C.both (a) and (b)
D.none of these

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52. The most efficient way to enclose a space is within a/an
A.sphere
B.cube
C.icosahedron
D.helix

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53. Which of the following is an example of rod-shaped viruses having their capsomeres arranged helically and not in the stacked ring?
A.Bateriophage M13
B.Bateriophage MV-L2
C.Bateriophage T2
D.Bateriophage T4

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54. During the first 10 minutes after injection of phage DNA, no phage can be recovered by disrupting the infected bacterium. This is termed as
A.eclipse period
B.rise period
C.latent period
D.burst size

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55. The function of a viral capsid is
A.protection against the viral genome from physical and enzymatic destruction
B.providing binding sites that enable the virus to attach to specific receptor sites on the host cell
C.serving as a vehicle of transmission from one host to another
D.all of the above

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56. Which of the following oncogenic viruses was first detected?
A.Rous sarcoma virus.
B.Epstein-Barr virus
C.Herpes simplex virus type 2
D.Human T cell leukaemia virus

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