1. the Immune System

2. Unit 12: The Immune System
“The war inside your body”
Immunity VS disease

3. The Immune System Function:
Recognizes foreign molecules and acts to immobilize, neutralize, or destroy them

4. Most of the time good prevails…

5. …Sometimes evil is too much!

6. What is the evil?
Pathogens
Harmful or disease causing organisms.

7. 5 Types of Pathogens (Largest to Smallest)
1. Parasitic Worms
2. Fungi
3. Protozoa
4. Bacteria
5. Viruses

9. the Immune System

10. 2 Types of Defenses Innate Defense and Adaptive Defense
(“Non-Specific”) (“Specific”)

11. “Non-Specific” Defense
Innate Immune system
“Non-Specific” Defense
When you were born you already had several mechanisms to prevent illness both Externally and Internally.

12. “Non-Specific” Defense
Innate Immune system
“Non-Specific” Defense
External Defenses:
1st Line of Defense - Surface Barriers
1. Integumentary System: Skin is a natural barrier that repels pathogens

13. “Non-Specific” Defense
Innate Immune system
“Non-Specific” Defense
External Defenses:
1st Line of Defense - Surface Barriers
2. Digestive System: High Acidity in stomach kills pathogens

14. “Non-Specific” Defense
Innate Immune system
“Non-Specific” Defense
External Defenses:
1st Line of Defense - Surface Barriers
3. Respiratory System: Mucus traps pathogens
I’m sorry your SNOT feeling well!

15. “Non-Specific” Defense
Innate Immune system
“Non-Specific” Defense
Internal Defenses:
2nd Line of Defense
Phagocytes: Engulfs/Destroys Pathogen at site of infection
Macrophages: “Big Eaters” engulfs cellular debris, foreign substances, bacteria, and cancer cells
Neutrophils: Most abundant, engulfs bacteria, they die in the process too

16. “Non-Specific” Defense
Innate Immune system
“Non-Specific” Defense
Internal Defenses:
2nd Line of Defense
Basophils: Releases Histamine in response to allergic reaction

17. “Non-Specific” Defense
Innate Immune system
“Non-Specific” Defense
Internal Defenses:
2nd Line of Defense
Natural Killer (NK) Cells: Actively scan the body for cells for “Self Antigens” (ID Badge). No ID badge? Cell is attacked! This is the body’s first line of defense vs Cancer.

18. “Non-Specific” Defense
Innate Immune system
“Non-Specific” Defense
Internal Defenses:
2nd Line of Defense
Inflammation Response:
A series of “Non-Specific” events that occur in response to pathogens. The response typically produces redness, swelling, heat, and pain in the target area. When a pathogen enter the body, the following events occur:
Vasodilation: Redness and Heat “Hyperemia”
Vascular Permeability: Swelling
Phagocytes Arrive: Engulf pathogens

19. “Non-Specific” Defense
Innate Immune system
“Non-Specific” Defense
Internal Defenses:
2nd Line of Defense
Fever Response
When Pathogens invade, the body produces “Pyrogens”, chemicals that force the Hypothalamus (regulates body temperature) to raise body temp.
Increased body temp creates a hostile environment for pathogen to live in.

22. Anatomy Test 12