Download Science 8 Immune System Mr. Birt Notes from handout: Immune

Science 8
Immune System
Mr. Birt
Notes from handout:
Immune System - system that fights germs (body defense system)
Primary Defense System
- The first barrier to germs entering your body
- It consists of things like skin, tears, earwax, saliva, gastric juices, cilia hairs, and mucous
- skin – body’s protective covering
- tears – drain dirt and germs from eye
- earwax – traps and drains dirt and germs from ear
- saliva and gastric juices – destroy germs in mouth and stomach
- cilia – fine hairs in nose, ears, and throat that trap particles of dirt
Secondary Defense System
- Fights germs, bacteria, and other disease-causing organisms inside your body, your
- white blood cells eat or engulf bacteria that have entered your body
- special white blood cells create particles called antibodies that attack specific germs
for which they were made
Questions from handout:
Primary Defense Systems
1. The nose is lined with small cilia and a sticky liquid called mucous.
2. The hairs and mucous filter and trap
foreign particles, and germs / dust / dirt.
3. Trapped dust and pollen “tickle” our noses. This makes us
sneeze.
4. How do sneezing and coughing help fight disease?
They expel (force out) germs.
5. Why should you always “cover” a sneeze or cough?
To prevent your germs from spreading to other people.
6. Harmful substances that reach the windpipe are trapped by
mucous
7. They are swept outward by microscopic hairs called
cilia
8. Cilia in the windpipe are always moving towards
the mouth and nose
Secondary Defense Systems
1. What kind of blood cells fight germs in the body?
white blood cells
2. What is happening in the diagram above?
The white blood cells are engulfing and destroying the germs
3. What chemical substance does the human body make to fight germs?
antibodies
4. What is happening in the diagram above?
Antibodies are attaching to germs
5. What body system is in charge of making antibodies?
The immune system