Question

The latest view for the origin of viruses is

• A. They have arisen from nucleic acid and protein found in primitive soup
• B. They arose from bacteria as a result of loss of cell wall, ribosomes, etc
• C. They arose from some bacteria which developed a nucleus only
• D. They are modified plasmids which are in fact the fragments of nucleic acids of the host

Answer 1

Answer: (D)

They are modified plasmids which are in fact the fragments of nucleic acids of the host

Viruses play an important role in horizontal gene transfer and genetic diversity. The evolution history showcases the origin of viruses as to have evolved from plasmids when pieces of DNA moved between cells. As big bits of cellular DNA became independent and some DNA stuck with cell genomes. Thus, the correct answer is option D.