immunology

phagocytes recognise the cell and destroy them using phagocytosis

pathogen is detected by phagocyte after being detected pathogen is engulfed into a vesicle inside the phagocyte lysosome fuse with vesicle and release digestive enzyme which destroys the already engulfed pathogen digested products diffuses into the the cytoplasm of phagocyte providing nutrition

response by cells to damage or infection involving the release of histamine from mast cells and accumulation of phagocytes in a damaged area. also involves cytokines and vasodialation.

mast cells

physical barriers phagocytosis production of chemical secretions inflammatory response

histamine is released by mast cells causing vasodilation and increased capillary permeability. the increased blood flow leads to an accumulation of phagocytes and clotting elements at the site of infection

vesicle within a phagocyte that contains digestive enzymes that destroys enzymes that destroys pathogens during phagocytosis

cells that produce histamine in response to tissue damage

general response to infection

bacteria, viruses or other organisms which can cause disease

releases of substances such as mucus, tears and saliva and stomach acid to help fight pathogens

closely packed epithelial cells in undamaged skin and inner linings of the digestive and respiratory systems; protects against entry of pathogens. they are found in these places because these are vulnerable sites of the body which come into contact with the enviroment

they are protein molecules that act as a signal to specific white blood cells causing them to accumulate at the site of infection

the additional blood supply makes the injured area red and inflamed and the swelling is caused by the capillary walls becoming more permeable which causes them yto leak fluid into neighbouring tissues

an accumulation of phagocytes show up at the damaged tissue rapid delivery of blood clotting chemicals to the injured area stops the loss of blood and prevents further infection and makes the start of the tissue repair process

mass cells are produced from the same stem cells as white blood cells

phagocytes are white blood cells that recognise pathogens and destroy them

they are produced by phagocytes

immunity is the ability of the body to resist infection by a pathogen or destroy the organism if it succeeds in infecting and invading the body

in allergy B lymphocytes become hypersensitive to normally harmless antigens such as those on pollen and nuts. the hypersensitive response produces the allergic reaction of conditions such as hay fever and peanut allergy

lymphocytes are the white blood cells that are involved in the specific immune response

lymphocytes respond to specific antigens on invading pathogens

lymphocytes have a single type of membrane receptor which is specific for one antigen.

antigen binding leads to repeated lymphocyte division resulting in the formation of a clonal population of identical lymphocytes