Tom Whitelaw Max McGill

43.1 Innate Immunity Invertebrates- They have physical and chemical barriers to guard against microbes, as well as cell based defenses. Including, in Insects, the ability to ingest microbes in the Hemolymph and cells can release antimicrobial peptides. Recognition Proteins Vertebrates- Skin and Mucous Barriers, phagocytes, low ph, lysomes, inflammation, antimicrobial proteins, compliment proteins, interferons and natural killer cells Some bacteria have an outer capsule that prevents recognition by killer cells and some can resist against degradation by lysozomes.

43.2 Acquired Immunity When pathogens are recognized, the body releases specific T and B cells to combat the threat. B cells recognize invaders by epitodes T cells recognize invaders by peptides

43.3 Cells B Cells produce antibodies that bind to antigens T Cells produce antigens which antibodies bind

43.3 Cell types Infection of body fluids are subjected to humoral responses and infection of body cells to cell-mediated responses Helper T Cells- makes CD4 which enhances binding to class II MHC molecule- antigen fragment complexes Activated Versions secrete proteins to destroy target cells by other lymphocytes Cytotoxic T Cells- Make CD8 enhances binding to class I MHC complexes Active versions secrete proteins that causedestruction of target cells

43.3 Cell Types B Cells- Generates plasma cells that secrete antibodies Infected once to gain acquired immunity Vacations Antigens on blood cells determine blood type. If different from the antigens that the body has they will be destroyed Organs have antigens too

43.4 Allergies are caused by the body attacking innate particles Some pathogens use antigenetic variation, latency and direct assault on immune system to weaken it HIV destroys helper T cells Cancers are more common with immunedeficencies and that is unclear whether it reflects reduced immune responses or increasing infections