What is Virus BMLT

Introduction of Virus



Virus


  1. Viruses are microbes that cannot be seen by wearing naked eyes.
  2.  The study of viruses is called virology.
  3. A single virus is called a virion
  4. Virus is the smallest, obligate, intracellular infective agent
  5. Two types of nucleic acids are found in virus.
  6. Viruses multiply by complex presses not by binary fission.
  7. Viruses do not do any metabolic activity outside the living cell.
  8. Viruses grow only on living cells, do not grow on artificial media
  9. No particular cell wall and cellular enzymes are found in the virus.

Size of Virus

  1. Its size is 10um- 300um
  2. Virus particles are called viruses.
  3. The largest virus is the small pox virus, whose size is 300 cm.
  4. The smallest virus is Parvo virus, whose size is 10-17um.

Structure:-

  1. Each cell contains nucleic acid which is coated by a protein called capsid.
  2. When nucleic acid is enclosed with capsid it is called nucleocapsid.
  3. The capsid is made up of a large number of protein subunits called capsomeres.
  4. Some viruses also have an envelope that covers the nucleic acid, which is a lipoprotein in nature.

Shape :-

There are different types of shapes like Brick Shape, Bullet Shape, Rod Shape etc.

Symmetry:- 

These are three types



  1. Icosahedral
  2. Helical
  3. Complex

1. Icosahedral

Aquilateral is triangular in shape with 12 vertices and corners and 20 facts.

Example :- Parvo Virus, Picorna Virus.

2. Helical :- 


The spring is written with nucleic acid and the capsomere connects with the spirals tube.

Example :- All RNA virus 

3. Complex :-

Both icosahedral and helical are not.

Example :- Pox Virus