Concept explainers
The genome of a virus consists of (a) DNA (b) RNA (c) prions (d) DNA and RNA (e) DNA or RNA
Introduction: An organism which has the characteristic feature to reproduce inside the living cell is called “virus”. They can survive without the host for a long period of time. When they infect the host cell they use the cell machinery of the host to reproduce. The size of the virus is extremely small and varies from 20 to 300 nm. The wide area of Earth is occupied by the viruses.
Answer to Problem 1TYU
Correct answer: The viral genome consists of deoxyribonucleic acid (DNA) or ribonucleic acid (RNA). Hence, the correct answer is option (e).
Explanation of Solution
Reason for correct answer:
Viral genome can be DNA or RNA, but it cannot be both at the same time. The virus can have single stranded or double stranded genome. This makes the virus classified into four categories: ss DNA, ds DNA, ss RNA, and dsRNA. Viruses can possess only a single type of genome at a time. Thus, the virus consists of either DNA or RNA.
Option (e) is given as “DNA or RNA”.
The virus can have either “DNA or RNA” as its genome. Hence, the correct answer is option (e).
Reason for incorrect answer:
Option (a) is given as, “DNA”.
Some of the viruses also possess RNA as their genetic material. This means some of the viruses still carrying RNA as their genome. Hence, option (a) is incorrect.
Option (b) is given as, “RNA”.
There are a variety of species still exists which consist of DNA as their genome. This signifies that the variety of viruses are having different genetic material other than RNA Hence, option (b) is incorrect.
Option (c) is given as, “prions”.
A prion is an organism which does not affect by any radiation and the presence of either DNA or RNA was not found in them. Thus, such a structure cannot be considered as the genome. Hence, option (c) is incorrect.
Option (d) is given as, “DNA and RNA”.
Viruses cannot possess both DNA and RNA as their genome at the same time. They can have either DNA or RNA in their genome. Thus, both of these genomic materials cannot be considered as genetic material in viruses. Hence, option (d) is incorrect.
Hence, the options (a), (b), (c), and (d) are incorrect.
The genome of the virus can have either “DNA or RNA” at a time.
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Chapter 24 Solutions
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