1. Viruses are
a) Inert outside their specific host cell
b) Obligate parasite
c) Passes through bacteria proof filter
d) All above statements are correct
Explanation: All above statements are correct
2. Who showed that virus can be crystallized out?
a) Ivanowsky
b) Beijerinck
c) Stanley
d) Pasteu
Explanation: Stanley
3. Virus contains
a) Protein
b) DNA
c) RNA
d) (a) and either (b) or (c)
Explanation: (a) and either (b) or (c)
4. Virus infected plants generally have
a) Single stranded DNA
b) Double stranded DNA
c) Double stranded RNA
d) Single stranded RNA
Explanation: Virus infected plants generally have single stranded RNA.
5. Viruses which infect animals have
a) Single stranded RNA
b) Double stranded RNA
c) Double stranded DNA
d) Any of the above
Explanation: Any of the above
6. Bacteriophage generally have
a) Single stranded RNA
b) Double stranded RNA
c) Double stranded DNA
d) Any of the above
Explanation: Bacteriophage generally have Double stranded DNA.
7. Capsomeres may be arranged in
a) Helical
b) Polyhedral
c) Ellipsoid
d) Either (a) or (b)
Explanation: Either (a) or (b)
8. In virus infected plants the following symptoms can be observed
a) Mosaic formation and stunted growth
b) Leaf rolling and curling
c) Yellowing and vein clearing
d) All of these
Explanation: All of these
9. Select the total number of diseases from the following which can be caused by virus in plant or
animals.
Mumps, Small pox, Rust, Smut, Herpes, Influenza, Potato spindle tuber, Red rot of sugar cane,
Turnip mosaic, Black rot crucifier
a) 4
b) 5
c) 7
d) 8
Explanation: 5
10. Potato spindle tuber disease is caused by
a) Virus
b) Viroids
c) Lichens
d) Fungi
Explanation: Potato spindle tuber disease is caused by Viroids.