Status of Viruses:
Viruses are considered as…….
a) living
b) non- living
c) both a and b
d) none of them
Explanation: lie on the border line between living things and non-living things
Why viruses are considered living things?
a) they possess DNA and RNA
b) they can reproduce
c) they undergo mutation and genetic recombination
d) all of these
Explanation: also they possess ability to infect other living things and show irritability
Why viruses are considered as non-living things?
a) they are sub cellular or non-cellular
b) they don’t respire or excrete
c) they can be crystallized and stored
d) all of these
Discovery of The Virus:
Who demonstrated by the late 1800s that bacteria cause many diseases of man and other organisms?
a) Louis Pasteur
b) Robert Koch
c) W. M. Stanley
d) both a and b
