July 7, 2021
Bacteria, Fungi and Viruses are the three types of micro-organisms that cause disease.
They reproduce rapidly because...
- humans are warm (37 degrees celsius)
- humans are moist
- humans have sugars on the surface of our cells
In I/GCSE, we need to learn details about micro-organisms that cause disease.
Bacteria
- Microscopic single-celled organisms
- Come in many shapes and sizes (BUT even the largest are only 10 micrometres long - 10 millions of a metre)
- Living cells
- Can multiply rapidly in favorable conditions
- Once inside the body, they release poisons or toxins that make us feel ill
Diseases caused by bacteria include:
- food poisoning
- cholera
- typhoid
- whooping cough
- gonorrhoea (a sexually transmitted disease)
Viruses
- many times smaller than bacteria
- among the smallest organisms known
- consist of a fragment of genetic material inside a protective protein coat
- can only reproduce inside host cells, and they damage the cell when they do this
Diseases caused by viruses include:
- influenza - flu
- colds
- measles
- mumps
- rubella
- chicken pox
- AIDS
That's the end of today's topic!