6. Influenza virus undergoes antigenic shift resulting in major antigenic changes by which of the following mechanisms?

A. Somatic recombination of heavy and light chains
B. Expression of several different capsule types
C. Changing the receptor binding canyon that docks with the host receptor
D. Reassortment of RNA segments from different influenza viruses

7. The nucleocapsid is covered by an outer membrane like structure called

A. envelope
B. covering
C. membronocapsid
D. all of these

8. Which type of interferon is produced by virus-infected cells?

A. α
B. β
C. Both (a) and (b)
D. None of these

9. Fluorescence microscopy can be used for the diagnosis of

A. Subacute sclerosing panencephalitis
B. Herpes simplex encephalitis
C. Rabies
D. All of these

10. Viral matrix proteins are

A. exposed on the surface of the virus
B. found mainly on naked viruses
C. anchor the envelope of enveloped viruses
D. part of the nucleoprotein core of viruses