MCQ
In some viruses, $RNA$ is present instead of $DNA$ indicating that
- Atheir nucleic acid must combine with host $DNA$ before replication.
- Bthey cannot replicate.
- Cthere is no hereditary information.
- ✓$RNA$ can transfer heredity material.
✓
Answer
Correct option: D.
$RNA$ can transfer heredity material.
d
Viruses are defined as infectious nucleoproteins. A complete virus particle is called virion whose main function is to deliver its $DNA$ or $RNA$ gesnome into the host cell, so that genome can be expressed by the host cell. In a particular virus either $DNA$ or $RNA $is genetic material, never both are present in a virus. Hence, viruses are: $(i)$ Double stranded $DNA$ or ds $DNA$ - Hepatitis B $(ii)$ Single stranded $DNA$ or ss $DNA$ - coliphage $(iii)$ Double stranded $RNA$ or ds $RNA $- Reo virus, wound Tumor virus $(iv)$ Single stranded $RNA$ or ss $RNA$ - Tobacco mosaic virus $(TMV)$
Viruses are defined as infectious nucleoproteins. A complete virus particle is called virion whose main function is to deliver its $DNA$ or $RNA$ gesnome into the host cell, so that genome can be expressed by the host cell. In a particular virus either $DNA$ or $RNA $is genetic material, never both are present in a virus. Hence, viruses are: $(i)$ Double stranded $DNA$ or ds $DNA$ - Hepatitis B $(ii)$ Single stranded $DNA$ or ss $DNA$ - coliphage $(iii)$ Double stranded $RNA$ or ds $RNA $- Reo virus, wound Tumor virus $(iv)$ Single stranded $RNA$ or ss $RNA$ - Tobacco mosaic virus $(TMV)$
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