Question

The protein coat of the virus is known as
(a) Capsid
(b) Virion
(c) Viroid
(d) Bacterial wall

Answer 1

Hint: The protein coat of the virus is the most outer part of the virus. It protects the genetic material of the virus. The protein coat consists of several oligomeric (repeating) structural subunits called protomers.

Complete step by step answer:
- Capsomeres are considered the 3- dimensional morphological subunits of the capsid (protein coat).
- Capsid proteins or viral coat proteins (VCP) are considered the proteins that make up the capsid. The nucleocapsid is called the capsid and inner genome.
- Capsids, according to their shape, are narrowly graded.
- Many viruses have either a helical or icosahedral capsid structure.
- Some viruses are enveloped, which means that a lipid membrane known as the viral envelope is filled with a capsid.
- The envelope from the intracellular membrane of the virus- host is obtained by the capsid; examples include the inner nuclear membrane, the Golgi membrane, and the outer membrane of the cell.
- New capsid subunits are synthesized using the cell's protein biosynthesis process after the virus has infected a cell and starts to replicate itself.
- Other viruses, especially more complex viruses with double- stranded DNA genomes, are assembled by capsid proteins into empty precursor procapsids, which have a single vertex specialized portal structure. - Viral DNA is translocated into the capsid through this portal.
So, the correct answer is ‘(a) Capsid’.

Note:
- The capsid functions are to: Safeguard the genome, the genome is delivered and, host to communicate with.
- A stable, protective protein shell must be assembled by the virus to protect the genome from lethal chemical and physical agents. These include sources of natural radiation, pH or temperature extremes, and enzymes that are proteolytic and nucleolytic.