Question

Which of the following viruses contains both DNA and RNA?
A) Cyanophage
B) Herpes Virus
C) Leuko Virus
D) Polio Virus

Answer 1

Hint: In the five-kingdom classification of Whittaker, there is no mention of some acellular organisms like viruses, viroids, and lichens.

Complete Answer:
Viruses are infectious agents, with a simple, acellular organization. They are the exception to the cell theory. The study of the virus is called virology. Viruses are connecting links between living and non-living entities. They have the properties of both living and non-living things. Viruses can reproduce only within the living cells and are obligatory intracellular parasites.

Now consider the options given above:
A) Cyanophage: Cyanophage belongs to three recognized families of double-stranded DNA viruses. They have a complex pattern of host ranges, are widely distributed, and can be readily isolated from marine and freshwaters.
Thus this option cannot be correct as it contains only DNA.
B) Herpes Virus: Herpesviruses have a unique four-layered structure, a core containing the large double-stranded DNA genome. Thus, This option is also treated as incorrect as it contains DNA only.
C) Leuko Virus: Leuko Virus is a retrovirus also referred to as the DNA-RNA virus. These viruses possess reverse transcriptase. This enzyme builds over the RNA genome and the process is called reverse transcription.
D) Poliovirus: Poliovirus is a member of the enterovirus subgroup, familyPicornaviridae. Picornaviruses are small, insensitive viruses with an RNA genome.
Thus, this option is also incorrect as it contains only the RNA genome.

Therefore option ‘C’ Is correct as it contains both DNA-RNA.

Note: Viruses are obligate parasites and are inert outside their specific host cell.