Disease

Disease is a poor state of health of the body.

There are two types of disease:Congenital inherited disease eg ________

Acquired these are 'caught' as a result of infection or a bad lifestyle.
Eg _____________

Infectious Diseases

Infectious diseases can be spread from person to person.

They can be caused by parasitic worms (tiny worms which live inside a host organism and cause disease) or microorganisms.

Most infectious diseases are caused by microorganisms, including bacteria, fungi, viruses and protozoa.

Bacteria

Bacteria are single-celled organisms. The largest bacteria are slightly larger than a red blood cell.

As the bacteria feed and grow they give off toxins, which make their host sick.

Examples: pneumonia, tetanus and food poisoning.

http://en.wikipedia.org/wiki/Bacteria

Fungi

Fungi are the largest of the four types of microorganisms.

Fungus = singular; fungi = plural.

Fungi can feed on living or dead matter.

Mould, mushrooms and yeast are all fungi.

Fungi release tiny spores which pass through the air and start new fungi (like seeds for plants).

Diseases caused by fungi include athletes foot, ringworm and thrush.

http://en.wikipedia.org/wiki/File:Fungi_collage.jpg

Athletes Foot

http://upload.wikimedia.org/wikipedia/commons/4/4a/Athletes.jpg

Viruses

Viruses are tiny organisms which can only live in host organisms.

Viruses force cells to make copies of themselves, and then spread them.

Unlike bacteria and fungi, viruses cannot be killed with antibiotics.

Examples include influenza (including H1N1 etc), the common cold, chickenpox, AIDS.

http://en.wikipedia.org/wiki/Virus

How Viruses Reproduce

http://www.flutrackers.com/forum/attachment.php?attachmentid=326&d=1148840493

Protozoa

Protozoa are single-celled organisms.

They are larger than bacteria and viruses and can grow as large as 1mm.

They are more complicated than bacteria and viruses and can do some things animals can do, eg move around.

Examples include Malaria and Amoebic dysentery.

http://peer.tamu.edu/curriculum_modules/properties/module_1/lesson_protozoa1.htm

http://www.mysimplecrib.com/wp-content/uploads/2011/08/Structure-of-an-amoeba.jpg

Diagram of Protozoa:

Work for Today, and Homework

Complete questions 1-5 on page 50 (not the extra).

Read pages 168-171 and the summary on page 162.

Answer questions 1,2,4,5 and 7 on page 172.

When you have finished, choose a disease and begin researching it. You must have found at least two good websites (remember Mr Farrow's talk) and have shown them to me to confirm your essay topic by the end.

If you haven't already, save a new copy of the G7 Diseases One World Essay Instructions, re-save it, share it with me and begin completing it.