L21 - the immune system Flashcards
what is the job of the immune system
repair damaged tissues
respond to infection
slow cancer growth
what is humoral immunity
secretion of protective substances eg antibodies into body fluids
what is cellular immunity
cellular response to infection (phagocytes etc)
list the physical barriers that prevent pathogen entry
skin
mucous
mucous membranes (cilia)
scabs
List chemical barriers that prevent pathogen entry
mucus
stomach acid
lysozymes in tears/saliva
briefly describe innate immunity
non specific
rapid
responds to infections (non self) & altered self (cancer)
can be humoral/cellular
what does the innate immune system promote
inflammation
briefly describe adaptive immunity
specific
slower than innate
humoral or cellular
has memory
list the cells involved in the innate immune system
- macrophages
2. neutrophils
describe features of macrophages
large
highly phagocytic
non specific (eat anything)
can produce new lysosomes
describe features of neutrophils
respond to infection
quicker than macrophages
die after disposing of target
what are the cells of the adaptive immune system
lymphocytes ( B&T cells )
what is the specific name for macrophages in the:
- liver
- bone
- kidney
- brain
- kupffer cells
- osteoclasts
- mesangial cells
- microglia
what does the adaptive immune system recognise?
antigens
where are lymphocytes found
circulating blood and lymph
where are lymphocytes activated?
in 2ndary lymphoid organs (mainly lymph nodes)
where are b cells produced
bone marrow
where are t cells produced
bone marrow
where do B cells mature
in bone marrow
where do T cells mature
in thymus
what is the general function of B cells
secrete antibodies specific to target antigen (humoral)
what is the general function of T cells
activated to induce direct cell mediated response by:
recruiting other cells
attacking themselves
how do T cells recognise antigens?
T cell receptors (TCR)
how many types of T cell are there
4
name the types of T cells
- helper T cells
- cytotoxic T cells (killer)
- regulatory T cells
- memory T cells
function of helper T cells
activate B cell response
activate the other 3 T cell types