1. Third Line of Defense Immune Response (Specific Defense)

2. Immune Response (Specific Defense)
A series of specific defenses that attack a particular disease-causing agent is called an Immune Response

3. Two Divisions of the Immune System
Humoral Immunity
Cell-mediated Immunity
Antibodies mark infected cells for death
Cells attack infected cells

4. Cells of the Immune System
Two types of cells recognize specific antigens:
B Lymphocytes and T Lymphocytes
B-Cell
T-Cell

5. Antigen
A substance on the surface of a pathogen that triggers an immune response is called an Antigen (Germ’s fingerprint)

6. Antibody Plasma cells produce antibodies
Antibodies circulate in the bloodstream and attack the pathogen causing the infection

7. Antibody
Antibodies are proteins that recognize and bind to antigens

8. Antibody
Antigen-Binding Sites
The site that the antibody binds to the antigen is called the antigen-binding site

9. Memory Cells
Some B-cells become memory cells, which are the antibody factory pre-programmed to respond to a returning antigen (i.e. vaccination)

10. Stop Here

11. Humoral Immunity
Plasma Cell
Antibodies
B-Cell
Pathogens
(Bacteria, Virus, Fungi, Worms, Foreign Proteins)
3. B-cells become Plasma cells, which produce antibodies against the antigen
Antibodies bound to pathogen
2. B-cell recognizes antigen on pathogen
4. Antibodies bind to the pathogen, marking it for death
1. Pathogen invades the body

12. Humoral Immunity
B-Cells - provides immunity against pathogens found in body fluids.