the immune response Flashcards
non specific immunity
phagocytes
specific immunity
lymphocytes
phagocytosis
a type of bc that carries out phagocytosis they are found in the blood and tissues and they are the first cells to respond to an immune system trigger inside the body
how are phagocytes attracted to the pathogen
any chemicals or debris released by the pathogen will attract the phagocyte towards it
lots of binding points of a phagocyte
to an antigen
why will the phagocyte change shape
to engulf the pathogen
what is a phagosome
the pathogen in the phagocyte is contained in a vesicle and is know as a phagosome
lysosomes fuse with phagosome
and release lysozymes’ which is a lytic enzyme which hydrolyses the pathogen
-destroys it and is absorbed by the phagocyte
apc
is a phagocyte which presents the pathogens antigens on the cell surface to activate t cells and acts as an antigen presenting cell
what are the two types of t cells
- cytotoxic t cells
- helper t cells
which type of response is associated with t cells
cell mediated response/ cellular immunity
are lymphocytes part of specific or nonspecific immunity
specific immunity
where are t cells made
made in bone marrow but mature in thymus
what do t cells only respond to
apc
helper t cells have receptors,,,
which bind to the antigens on the apc
what happens to helper t cells once activated
they divide by mitosis to replicate into large number if clones
-remain a helper t cell and activate b lymphocytes
some stimulate phagocytes
-or form memory cells for that shaped antigen
clo0ne helper t cells differentiate into what
-either remain a helper t cell and activate b lymphocytes
and stimulate phagocytosis or form memory cells into that specific shaped antigen or become cytotoxic t cells
what do cytotoxic t cells do
they release a protein called perforin which causes pores in the cell so any substance can leave or enter the cell which causes cell death
what is b cells and antibodies linked to
humoral response
where do b cells mature
bone marrow
b cell activation
divides into plasma cells by clonal selection
what happens when antigens in the blood colli9de with their complementary antibody on a b cells
the b cell takes the antigen by endocytosis and presents it on its cell surface membrane
what happens when a b cell collides with a a helper t cell
this actives b lymphocytes to go under clonal expansion and clonal selection
what do plasma cells do
make antibodies specific for that antigen
what do b memory cells do
divide rapidly into plasma cells so when reinfected with the same pathogen can make large numbers of antibodies rapidly
memory cells vs plasma cells
plasma cells are short lived and memory cells can stay for decades
memory cells do not make antibodies!
they will divide by mitosis and make plasma cells rapidly if they collide with a antigen they have previously encountered .
antibodies are proteins
quaternary structure bonded with disulphide bonds
variable region
will change its tertiary structure to change its shape to become specific for its antigen
constant region
same for all antibodies
agglutination
antibodies will will bind to the antigens to create antigen antibody complex
antibodies are flexible and can bind to multiple antigens to clump them together
