VIRUSES

Viruses are microscopic organisms.

SHAPES:

Viruses exist in three kinds of shapes:

(1) ROUND VIRUSES:

(2) ROD LIKE VIRUSES:

(3) CRYSTAL LIKE VIRUSES

STRUCTURE OF VIRUS:

The body of virus is chemically made up of proteins and DNA.

* Outer protein coat.

* Inner core of DNA.

Viruses are heterotrophic and cannot prepare their own food. Thus they get food from other living organisms as parasite and produce many diseases in animals and plants.

DISEASES PRODUCED BY VIRUSES IN MAN:

* Polio.

POLIO VIRUS

* Influenza

INFLUENZA VIRUS

* Measles

MEASLES VIRUS

* Small pox.

SMALL POX VIRUS

Among plants, virus destroy leaves of tobacco, potato, tomato and cauliflower.