Question

Describe the shape of a viral particle?

Answer 1

A complete virus particle (also called virion) consists of nucleic acid (the core of the virus,which make up the genetic information in the form of RNA or DNA) surrounded by a protective coat of protein called capsid. The capsid is made up of protein subunit called "capsomeres" which are in turn made up of subunits called "protomers". These proteins are encoded by the viral genome and its shape serve as the basis for morphological distinction.

A virus structure can be of the following: Helical , Icosahedral, enveloped and complex.

Helical virus: It's capsid is shaped into a filamentous or rod -shaped structure. This type of shape has a central cavity that encloses the nucleic acid.

Icosahedral : These virus consists of identical subunit that make up equilateral triangle that are in turn, arranged in a symmetrical fashion.

  Enveloped: This virus is a icosahedral or helical structure surrounded by a lipid bilayer membrane, meaning that the virus is encased or enveloped.

Complex: This virus structure is made up of combination of icosahedral and helical shape. They may have a head-tail morphology .( Example- bacteriophage)