In some viruses, $RNA$ is present instead of $DNA$ indicating that
their nucleic acid must combine with host $DNA$ before replication.
they cannot replicate.
there is no hereditary information.
$RNA$ can act to transfer heredity.
In chromosomes, the material controlling heredity is
Genes are
Name any three viruses which have $RNA$ as the genetic material.
The scientists involved in discovery of $DNA$ as chemical basis of heredity were
$DNA$ contains