5 - Cell Recognition and the immune system Flashcards
what is recognised as non-self? (4 things)
- pathogen
- toxins produced by pathogen
- abnormal body cells (cancer cells)
- cells from other organisms
how do lymphocytes recognise self/ body cells in FEOTUS WOMB?
- collide exclusively with body’s own material
- some lymphocytes have receptors for body cells
- those lymphocytes die or are surpressed
- only lymphocytes that respond to foreign material remain
how do lymphocytes recognise self/ body cells in ADULTS - BONE MARROW?
- initally lymphocyte only encounter self antigen (collision with own self)
- lymphocytes that responds kills itself (APOPTOSIS)
- lymphocytes that didn’t respond/ respond to foreign antigen REMAINS
clonal selection
chance that one RECEPTOR on surface of one of the lymphocytes will have a complimentary shape to an ANTIGEN on surface of the pathogen, so the process of choosing THAT lymphocyte
clonal expansion
correct lymphocyte replicate by mitosis (genetically identical offsprings)
where does phagocytosis happen?
blood and tissue fluid
what type of process is phagocytosis
phagocytosis is a type of endocytosis
phagosome
vesicle with the engulfed pathogen inside the phagocyte
macrophage
type of phagocyte
humoral response
- antibodies released plasma cells (mature B-cells) as a response go antigens
- in bodily fluids
cell mediated response
- stimulates cytotoxic T cells to destroy cells infected by pathogen infections (APCs) and cells that have suffered mutations
what are naïve B cells?
NOT YET activated B cells
why antibody binds to pathogen?
- antibody has tertiary structure
- complementary to binding site on protein
what do plasma cells do?
- RELEASE antibodies
where do B-cells mature?
Bone marrow
