Chapter 17 Flashcards
Defenses against any pathogen
Innate immunity
Induced resistance to a specific pathogen
Adaptive immunity
How to get adaptive immunity
- Getting sick
- Vaccines
Also called adaptive immunity
Specific immunity
Bodys third line of defence
Specific immunity
Specific immunity due to two types of lyphocytes
- B lymphocytes (B cells)
- T lymphocytes (T cells)
A substance that causes the body to produce specific antibodies or sensitized T cells.
Antigen (ag)
Examples of antigens (5)
- Bacterial capsules
- Cell walls
- Flagella
- Fibriae
- Toxins
Specific region of Ag that combines with products of the I.S. Binding sites.
Antigenic determinant
Is a globular protein made in response to a specific antigen.
Antibody (ab) or Immunoglobulin (Ig)
Are chemical messengers released primarily by helper T cells.
Cytokines
Produce antibodies
B cells
Secrete cytokines
T cells
Antigen presenting cells
- Macrophages
- Dendritic cells
What happens if you don’t have cytokines?
No immunity.
How does the immune system recognize itself/nonself?
Markers called Major Histocompatability Complex cells. Monitor the expression of MHC class 1 molecules. If the cell has class 1 that is empty it is left alone. I it presents with a virus it is killed on contact.
Cells of the specific imune system
Lymphocytes
Stay in bone marrow. Mature in bone marrow and acquire receptors (specific shape). Programed to make specific antibody. Secrete antibodies in fluids. Involved in humoral immunity.
B cells
Acquire receptors (Specific shape) in thymus. Cellular (cell to cell interaction). Antigen must be presented to them.
T cells
B Cell receptors can recognize ag in its natural state. For example: ……………
Before these agents enter the cells.
- Bacteria in blood.
- Viruses in blood.
- Toxins in the blood.
When a B cell encounters its triggering antigen it gives rise to what?
- Plasma cells
- Memory cells
Shape of Antibody
Y
2 heavy chains
2 Light chains
Y arms vary greatly (To accommodate millions of possibilities)
Functions of antibodies?
Agglutination (Group together) Opsonization Activation of complement Neutralization Antibody dependent cell mediated cytotoxicity
Most abundant antibody (in blood)
IgG
