1. The Immune System

2. What is it?
The body’s defense against disease-causing organisms, malfunctioning cells, and foreign particles

3. 1st line of defense: Involves several kinds of physical and chemical barriers.
chemical: sweat, tears, saliva, mucus, stomach acid
physical: skin, lining inside the nose and ears

4. 2nd line of defense: The Inflammatory Response
Swelling, redness, warmth, and pain in the area of an infection.
An increased blood flow attracts white blood cells to infected area.
2nd line of defense: The Inflammatory Response

5. 3rd line of defense: The Immune response
Those that get through the first and second lines of defense trigger the production and release of antibodies (proteins that latch onto, damage, clump, and slow foreign particles).
New particles take longer to identify, and a person remains ill until a new antibody can be made.
Old particles are quickly recognized, and a person may never become ill from that invader again. This person is now immune and can’t get sick again.

6. Vaccines
Purposely introduces weakened bacteria or viruses into the immune system to produce immunity.
Because the invader has been killed or weakened, minimal symptoms occur
Have eradicated or severely limited several diseases from the world, such as polio and smallpox