1. The Immune System Topic 14

3. 1st Line of Defense Chemical & Physical Barriers

4. Pathogens are blocked
Skin prevents pathogen from entering
The nasal passages trap pathogens with hair and mucous.
The stomach acid has a pH of about 2. This is too acidic for many pathogens and will prevent them from functioning.

5. 2nd Line of Defense Inflammatory Response
The damaged area swells due to white blood cells, called phagocytes, responding to the site of infection.
Temperature rises in order to denature proteins in the pathogens, and prevent infection.

6. Pathogen- anything which can cause an infection (bacteria, virus, fungus, protists)
Antigen- Identifying proteins found on a pathogen. Each pathogen has a unique antigen!
Antibody- Specialized protein which binds to a specific antigen identifying it for destruction.

7. 3rd Line of Defense Immune Response

8. 2 Types of Lymphocytes T cells- Identify the pathogen
each T cell recognizes a specific antigen.

9. 2 Types of Lymphocytes B Cells- Produce Plasma cells and Memory cells
Plasma cells produce Antibodies
Memory cells remember the antigen and matching antibody.

10. Immune Response

11. Immune System Defender Game: http://nobelprize

12. Immunity
Active Immunity- The body produces its own antibodies after having an encounter with a specific pathogen.
Passive Immunity- Temporary immunity, antibodies are passed into the body from another source.

13. Vaccines
Vaccine- A dead or weakened pathogen introduced to the body. This allows the body to produce antibodies for that pathogen.

14. Interactive Making Vaccines: http://www. pbs

15. Immune System Disorders
Allergies- immune system over reacts to an allergen. Histamine is released- triggers an inflammatory response.

16. Immune System Disorders
Asthma- inflammation of the respiratory tract.

17. Immune System Disorders
Autoimmune Disease- immune system does not distinguish between self and non-self.
Rheumatoid Arthritis
Multiple
Sclerosis
Diabetes

18. HIV & AIDS HIV- attacks the T cells
Weakens the immune system, leads to development of AIDS