Innate (non specific) Defense
1st line of defense: Skin, mucus membrane attack foreign substances without activating the immune system.
2nd Line of Defense: inflammation and anti -microbal, protein and phagocytes.
Adaptive (specific) defense.
includes humeral (B-cells) cell mediated (T-cells) immunity specific respone. They are systemic and require immune activation. This mya generate memory and are specific to particular pathogen.
Protective function of surface epithelia.
membrans that are difficult to penetrate . Made of stratified epithelium , keratinzed and waterproof. Sebacous glands secret sebum which is acidic and kills most bacteria.
leukocytosis( increase wbc) increase the presences of wbc which release inflammatory chemicals such as histamine.
increase leakage of blood vessels. Heat, redness, pain and swelling are a result of vasodilation.
importance of phagocytes and natural killer cells in non specific defense.
Both and engulf pathogens and destroy cancerous cells without activating the immune system.
secreted by virus infected cells and makes other cells less likely to become infected by virus.
What causes a fever?
Is caused by pyrogen molecules released by leukocytes which reset the hypothalmus to higher temps.
1. protect the body by increasing leukocytosis.
2. slows the reproduction of bacteria and viruses.
The role of macrophages and antigen-presenting cells in adaptive immunity.
Macrophages non specifically engulf pathogen and display anti gentic determinate on there class II MHC proteins. At that point phagocytes are called APC and there job is to seek and activate lymphocytes with receptors that are complementary to the anti genetic determinate.
lymphocyte are programmed to ignore body cells. baring self pepetids on there class I mhc Protein.
Cell mediated immunity which is when pathogenes or pathogen infected body cells are distroyed by t cells.
B lymphocytes differntiate into plasma cells. which produce antibodies against pathogens in the body fluid.
recount the roles of plasma cells and memory b cells in humoral immunity.
memory b cells become active secondary immune respone. (2nd time you see the same pathogen)
the organism produce antibodies themselves in generate memory its systemic and its specific are antigenic determinate.
2 types of active immunity
Naturally occurred-which is getting sick
Artificial -vaccine with weakened pathogen.
Another organism produces the antibodies. No Memory and immunity lasts about a week.
2 types of of Passive Immunity
Natural-passed from mother to fetus via breast milk or through palcenta.
Artificial-Injection with just antibodies.
secondary immune response.
Antibody levels peak within 3 days memory b cells and anitbody levels are higher in blood plasma longer.
4 classes of organ transplant
1. autograf (self to self)
2.isograf (from identical twin)
3.allograft (among same species)
4.Zinograft (across species)
HIV infects CD4 cells and weakens the immune system making you more susceptible to diseases.