The parts in the order of labelling are:
A - Envelope
B - Genome
C - Capsid
D - Spike
The figure shows the general structure of an encapsulated animal virus.
- The envelope is an outer layer that surrounds the viral particle. It is derived from the host cell membrane during the process of viral replication or release.
- The genome of a virus is its genetic material, which can be either DNA or RNA. This genetic material contains the instructions necessary for the virus to replicate and produce new viral particles.
- The capsid is the protein coat that surrounds and protects the viral genome. It is composed of protein subunits called capsomers, which self-assemble to form the capsid structure.
- Spike proteins, or viral glycoproteins, are often present on the surface of the viral envelope. These proteins play a crucial role in the attachment of the virus to specific receptors on the host cell surface.
The envelope, genome, capsid, and spike proteins are integral components of encapsulated animal viruses. The specific arrangement and composition of these components vary among different types of viruses, influencing their structure, function, and interactions with host cells.