1. The Immune System

3. Disease Transmission Robert Koch… “father of disease”
-research focused on anthrax
-Koch’s Postulates:
rules for determining the cause of a disease or illness.

4. Human Diseases and How They Are Transmitted
AIDS HIV Intercourse, contaminated syringes
Common Cold many viruses air, person to person
Malaria protozoan parasites mosquitoes
Measles paramyxovirus air, person to person
Botulism Clostridium botulinum contaminated food

5. Infectious Diseases -Pathogens – foreign particles
Ex. Viruses + bacteria
-Multiply in the body to cause infection
-Come into contact with the body by:
Air
Food
Water
Person-to-person contact
Animal bites

6. NonSpecific Defenses...First Line of Defense
Skin – prevents entry
Oil – traps and kills invaders
Mucous Membranes – epithelial tissue that protect the interior surfaces of the body.
Tears
Saliva
Ear wax
Hair/Cilia

7. Second line of Defense:
If a pathogen penetrates the first line of defense...
1. Inflammatory Response: series of reactions that suppress infection and speed recovery. a. Histamine released (Increases blood flow to site of injury/infection; can cause redness, swelling, warmth, and pain)
b. Phagocytes – type of white blood cell.
Neutrophils & Macrophages – attack pathogens
Natural Killer Cells – attack pathogen infected cells.
2. Complement System – using proteins to fight off pathogens
3. Interferon - protein that inhibits reproduction of viruses
4. Fever - sign body is responding to infection; suppresses growth and reproduction; promotes action of white blood cells.

8. 2. Thymus – gland in the chest 3. Lymph & Lymph Nodes
The 3rd Line of Defense: Specific Defenses against a specific pathogen.
Immune System – cells and tissues of your body that recognize and fight off pathogens.
1. Bone Marrow
-Produces white blood cells lymphocytes
-Two types: B cells & T cells
2. Thymus – gland in the chest
-Place of maturation of T-cells
3. Lymph & Lymph Nodes
-Filter pathogens, lymphocytes

9. -Contain lymphocytes which are important for antibody production.
4. Spleen
-Filters pathogens from blood
5. Tonsils & Adenoids
-Contain lymphocytes which are important for antibody production.

10. The Immune Response..two pronged attack!
The Immune Response begins with the recognition of an Antigen (pathogen).
-differing response based upon surface proteins on the antigen.
-Begin with helper T-cells (lymphocyte) binding with macrophages to fight pathogens.

11. 1. Cell-Mediated Immune Response
-Cytotoxic T-cells & suppressor T-cells
-destroy infected cells
-shut down response after pathogens are cleared
2. Humoral Immune Response
-B cells change into plasma cells and produce antibodies.
Antibodies – chemicals that binds to antigen to disable the pathogen (block reproduction).
-Antigen specific
-Stores antibodies for the future use

12. Primary & Secondary Immune Responses
Some B cells turn into memory cells
Lymphocytes that will not respond the 1st time they meet an antigen, but will recognize and attack with later infections
Explains why you get most diseases only once
Primary Immune Response
First time the body encounters an antigen
Memory cells produced for that specific antigen
Secondary Immune Response
Later infection by the same pathogen
Memory cells respond faster and stronger
Exception: Cold and Flu viruses

13. Immunity & Vaccination
1. Immunity-the ability to resist an infectious disease
Memory cells
Vaccinations
2. Vaccine-solution that contains a dead or weakened pathogen
Body produces primary immune response
Booster shots

14. Problems of the Immune System:
Allergies
Asthma
Autoimmune Diseases- immune system attacks your own body cells. (lupus, MS,
type I diabetes, rheumatoid arthritis)

15. *PLAY DISCOVERYEDUCATION VIDEO*
HIV and AIDS
AIDS- Acquired Immunodeficiency Syndrome
The immune system loses its ability to fight off pathogens and cancers
AIDS results from infection by HIV
HIV-Human Immunodeficiency Virus
Destroys Helper T cellscripples the immune systemleads to AIDS
Opportunistic Infections-illnesses caused by pathogens that produce disease in people with weakened immune systems
Usually these pathogens don’t create problems in healthy people
HIV does NOT cause death, but AIDS is fatal
Death caused by weakened immune system’s inability to fight opportunistic infections and cancers
HIV is transmitted by body fluids and contaminated needles
*PLAY DISCOVERYEDUCATION VIDEO*

16. Summary of Cell Types: