Natural Defenses
Name the four defenses of the body?
Barrier, cellular, inflammatory, and immune
How do barrier defense work and name three examples.
Anatomical barriers exist to prevent the entry of foreign pathogens.
Skin, mucous membranes, Gastric Acid, and the Major Histocompatibility Complex (MHC)
How do cellular defenses work and name 3 examples.
Stem cells in the bone marrow produce leukocytes and myelocytes. Lymphocytes consist of T cells, B cells, and natural killer cells. Myelocytes can develop into any number of cells and are important in both the basic inflammatory response and immune response.
Neutrophils, Basophils, Eosinophils, and Monocytes/Macrophages.
How does the inflammation process work? Explain briefly the three systems of inflammation.
When injury occurs activation of a chemical called factor XII or Hageman factor occurs. Factor XII is responsible for three systems.
Kinin System - Activates kallikrein which causes the precursor substance kininogen to be converted to bradykinin and other kinins. Bradykinin causes local vasodilation and changes capillary permeability, which brings more blood to the injured area and allows white blood cells to escape into the tissues. It also stimulates nerve ending to cause pain, which alerts the body to the injury.
The Clotting Cascade - initiates blood clotting
The Plasminogen System - initiates the dissolution of blood clots.
How does immune response occur and name the cells involved.
Immune response is more specific. It works by memorizing a disease and releasing cells that specifically know how to kill that type of cell.
T-Cells - T-Cells are programmed in the thymus gland and provide what is called cell-mediated immunity. They develop into three types of T-Cells. Effector/Cytotoxic T-Cells they release cytokines that either destroy the cell or mark it for termination. Helper T-Cells respond to chemical indicators and send in the troops. Suppressor T-Cells suppress immune response.
B-Cells are programmed to identify specific antigens. When it finds a specific antigen it become a plasma cell which then produces antibodies.
Natural Killer Cells blows up foreign contaminates.