Question

21. Which of the following is a property of viruses

A. They are infectious cellular pathogens

B. They contain a genome of DNA and RNA surrounded by a capsid

C. They are facultative intracellular parasites

D. They only infect animal cells

E. All of the above

F. None of the above

22. (−)ssRNA is transcribed into (+)ssRNA using which of the following?

A. RNA polymerase encoded by the host cell

B. RNA polymerase encoded by the virus

C. DNA polymerase encoded by the host cell

D. DNA polymerase encoded by the virus

23. Which of the following is true regarding retroviruses

A. The integrated viral genome is called a prophage

B. The host reverse transcriptase converts the RNA to cDNA

C. The host machinery directly translates the viral RNA

D. All of the above

E. None of the above

24. Enveloped viruses

A. Are surrounded by host cell phospholipids

B. Are only released through exocytosis

C. Contain icosahedral capsids

D. Are the only viruses that contain attachment spikes

25. All of the following are methods of viral genome release into the cell except?

A. Direct injection of the genome following surface attachment of naked virus

B. Membrane fusion to endocytic vesical of a naked virus

C. Lysis of an endocytic vesical by an enveloped virus

D. Capsid release into cell by cell membrane fusion of an enveloped virus

E. All of the above are methods of release

Answer 1

21) B option is correct

It is having genomic material DNA and RNA surrounded by capsid protein

22) B option is correct

(+) ssRNA strand of virus is converted into (+)ssRNA by RNA polymerase of virus synthesized once it infected into host.

23)B option is correct

Host reverse transcriptase converted RNA into DNA.

Retro virus are those viruses which convert RNA converted into cDNA . Like HIV

24) C option is right

Ecosahedral shape of which capsid is made up of.

25) D option

Capsid released into cell by cell membrane fusion of an envelop virus does not take place as capsid remain outside while infection and it inject only genomic material or whole virus goes inside along with vesicle by process of endocytosis.

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