pp. 961-966. lymphatic system spleen lymphocytes 1. b-cells: wbc that mature in bone marrow 2....

PP. 961-966

lymphatic systemspleen lymphocytes 1. B-cells: wbc that

mature in bone marrow 2. T-cells: wbc that

mature in thymus

There are many different lymphocytes (wbc)

Each have receptors for different antigens (markers) Antigen: Identifies cell as foreign

2-part attack Cell-mediated: Killer T-Cell production Humoral: B-Cell production

Starts with an initial response

Initialresponse

HumoralB-Cell

production

Cell-mediatedT-Cell

production

1. macrophage engulfs pathogen and puts antigens on its surface2. Helper T-cell binds to antigen

3. Macrophage releases a chemical (INK-1) which causes the Helper T-cell to release INK-2

Initialresponse

HumoralB-Cell

production

Cell-mediatedT-Cell

production

INK-2INK-2

INK 2 stimulates the production of more Helper T Cells and Cytotoxic T Cells

Cytotoxic T Cell (killer T cell): kills infected body cells.

Initialresponse

HumoralB-Cell

production

Cell-mediatedT-Cell

production

INK-2 causes complimentary B-cells to divide

Most B-cells change to plasma cells

Plasma cells produce antibodies Y-shaped protein that deactivates

pathogen and clumps them making it easier for macrophages to engulf and destroy them.

Some B-cells become memory cells and store information about pathogen Body’s long term defense system

When exposed to pathogen a 2nd time, memory cells immediately recognize and destroy it before it causes illness.

primary: 1st time body encounters pathogens

secondary: 2nd time body encounters pathogen with memory cells (leftover B-cells and T-cells)

Immunity: ability to resist an infectious disease

Vaccination: introduction of antigens into body to cause immunity

Vaccine: solution of dead or weakened pathogens that contains pathogens Antigens produce a primary immune

response Memory cells created provide quick

secondary immune response if antigen enters body again.

http://highered.mcgraw-hill.com/sites/0072507470/student_view0/chapter22/animation__the_immune_response.html

Some Diseases that have been controlled through vaccines: polio, measles, mumps, tetanus, and small pox