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define viruses

Define viruses

Viruses

The word viruses are derived from a Latin word venom which means poisonous. During (1822-1985) Louis Pasteur and Robert Koch used the viruses as a poison which is associated with diseases and death of living organism. No,, viruses are recognized with protein and nucleic acid that are able to replicate in the body of host and spread different diseases in their host.

Virology

The study of viruses is known as virology.

Structure of Viruses

Viruses contain nucleic acid and and are surrounded by aa protein coat known as capsomers. The number of these capsomers ar different in different viruses. Herpes viruses contain 162 capsomers and 252 capsomers are present in adenoviruses.

Largest Virus

Poxviruses are known as largest viruses.

Characteristics of Viruses

Viruses are well known due to spreading small infectious diseases which are only seen under electron microscope clearly. The maximum size of viruses is 250nm such as poxviruses which 10 to 1000 times smaller than bacteria.
Viruses can pass through pores?
Viruses are 10 to 1000 times smaller as compared to bacteria so, viruses are easily pass through small pores but bacteria not.
First Viral Disease

First viral disease wah cowpox which was developed in milkmaid.. In 1796 Edward Jenner first vaccinated 8 years old child.

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