Viruses


Micro-organism:The organism cannot be observed with naked eye,we need magnifying device or microscope.Those organisms that cannot be seen with naked eyes are called microorganisms.
Group of microorganisms:
Micro organisms form a heterogeneous group which includes different kind of organisms.They are given below:
1)Virus
2)Bacteria
3)Cynobacatria
4)Protozoa
5)Some algae
6)Some fungi
How metabolism is related to growth??
Metabolism——->Energy——->New protoplasm——–>cell size———>cell division————>Increase the cell growth
VIRUS:On the base of structure they range from sub-cellular to cellular.E.g.Virus
MEANING OF VIRUS;It is a Latin word.It means poison.
VIRUS..LIVING OR NON-LIVING?????????
They have character of both living and non living thing.Structurally they aren’t like a cell.It is sub cellular and is made up of only protein and nucleic acid.They also form crystal outside the body of host.However when they enter the body of any living organism,they reproduce like living organism but outside the body of living organism it cannot reproduce.They are parasites,these character show that virus is living or non-living.
NUTRITION:
All viruses are parasites and cause different diseases in their hosts.
DISCOVERY OF VIRUS:
Virus was discovered by Iwanowsky  in 1892.He demonstrated that infection of a healthy plant by the juice from a diseased plant occurred even after the juice had been filtered through finest bacterial filters and that the infective matter multiplied abundantly in the new host.He was the first to give a clear-cut evidence of a virus and for the first time the existence of invisible disease producing agencies,smaller than anything yet known was postulated.This agent was later called”Virus”.
SIZE:
Viruses are in size range from 0.01um to 0.3um.
SHAPE:
Viruses vary in shape.Some are round,rod,polyhedral while some are tadpole.
STRUCTURE OF VIRUS:
Image
Image
Viruses are different in shape but all are made up of two parts;
1)Coat
2)Core
COAT:
The outer coat is composed of protein.
CORE:
The inner core is made up of DNA or RNA.They are never together in a virus.The outer coat determines the shape or structure of virus.E.g.Bacteriophage protein.
Coat consist of two parts;
Head and tail
They also have protein.In inner core of head,it contains DNA.
VIRAL DISEASE:
Viruses produce many diseases in plant and animals.
DISEASE IN PLANT:
Ring spots in different plants.
Beet yellow in sugar beet.
Mosaic disease in tobaco,potato,tomato,cabbage and bean are the various viral diseases in plants.
DISEASE IN ANIMALS:
In man common diseases are:
Cold,influenza,small fox,yellow fever,polio,hepatitis and AIDS.
HOW VIRUS IS TRANSMITTED?
In human being they are transmitted by many ways E.g.through droplet produce on cough and sneezing,through contact by air,contaminated water,food through insect, by reuse of already used injections and unsterilized surgery equipment.
______________—————————–______________________—————————–______________________

Advertisements

Leave your precious Thoughts

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s