||by nojhan on Flickr||
- Micro-organisms are tiny living things.
- They are present in the air, in water and in our bodies.
- They need food, water & warm conditions to grow.
- Some micro-organisms are harmful and cause disease & others make food go bad.
- However, not all micro-organisms are harmful. Many are used in the brewing, baking and dairy industries.
||by kaibara87 on Flickr||
Four different types of micro-organisms are:-
Bacteria are single celled organisms.
They are able to live in body tissues between cells.
They need food, warmth and moisture to grow.
They can multiply quickly by cell division if conditions are right.
Bacteria cause diseases such as whooping cough, tuberculosis, pneumonia and cholera.
Salmonella is a bacteria that can cause food poisoning.
|Fungi @ Dunwich Heath
||by timparkinson on Flickr||
- Fungi are the largest of the four types of micro-organism.
- The fungus makes fine threads, which invade cells and absorb nutrients from them.
- Fungi can live on decaying substances or in living tissue.
- They include moulds, which live on rotting food.
- The diseases caused by fungi include athlete's foot, ringworm and thrush.
||by kat m research on Flickr||
- Viruses are the smallest micro-organisms.
- They can only be seen using the most powerful microscopes.
- Viruses invade and then destroy living cells.
- Viruses are responsible for many diseases such as : influenza, measles, chickenpox and smallpox.
|Acanthamoeba cyst in brain tissue||by prep4md on Flickr|
- Protozoa are single celled organisms like amoeba.
- They are larger than viruses and bacteria.
- Protozoa feed by absorbing nutrients from their surroundings.
- Malaria and amoebic dysentery are caused by protozoa.