Structure of a virus
Viruses are very simple in structure and are made up of only two or three components:
- Genetic material is the hereditary information of a virus. It is a collection of genes and carries all the information needed to allow the virus to replicate in a cell. The genome can be either RNA or DNA.
- The capsid, or the protein coat, surrounds the genome. It consists of protein subunits called capsomeres linked to make a 3D structure.
The viral envelope surrounds some, but not all viruses. It is made up of a modified cell membrane obtained from the host cell as the virus leaves.
The viral envelope is also known as the lipid envelope because it is formed of lipids.