Immune responses Flashcards
what are immune defences and how are they organised
innate immunity - inflammatory responses
acquired immunity - hormonal response, not strong, can be overwhelmed easily
what are the key features of the innate immune system
pathogens, they cause diseases which affect animals
when the body recognises foreign bodies they start to produce immune proteins
what barrier defences are there and how do they function
nonspecific external barriers (skin),
they act as a fast acting
low pH that prevents growth of many bacteria
Lysosome?
what is the process is it called when cells of the immune system engulf pathogens by endocytosis, the vacuole forms, the vacuole and lysosome fuse together, pathogens are then destroyed and then the debris from the pathogens are released.
phagocytosis
what is a macrophages
phagocytic cells derived from monocytes, they circulate in the blood and are found in tissue cells
what is neutrophils
Phagocytic cells consisting of over half of all leukocytes, they are short-lived and destroy cells very fast
what protein is it called when they create pores in the plasma membrane of the target cell
perforins
how do inflammatory responses work, give some examples
they work like pain and swelling and fever
it is signalled by mast cells, which release histamine
signalling molecules
name 5 key characteristics of acquired immune system
develops by experience
slower response
highly specific
long-term memory component
lymphocytes
where do T and B cells mature
T cells - responsible for cell-mediated response: infected body cells
B cells - involves in hormonal response: antibodies are produced
what is it called:
small accessible parts of an antigen that binds to an antigen receptor called an epitope
antigens
how do B and T cells recognise antigens
each is specialized to recognise a specific type of molecule
they bind specifically to each cell
what does MHC stand for
Major Histocompatibility complex
how do helper T cells work in acquired immunity
they stimulate cytotoxic T cells to kill infected body cells
how do antibodies function
they have an antigen binding site and a constant region
specific to antigens
