KA6 Flashcards
(29 cards)
Lymphocytes respond to specific
Antigens on invading pathogens
What are antigens?
Molecules often proteins located on the surface of cells that triggers a specific immune response
Lymphocytes have a single type of membrane receptor which is
Specific for one antigen
The specific lymphocyte undergoes repeated
Cell division
This results in what
Clinal population of identical lymphocytes
B lymphocytes produce
Antibodies againts antigens and this leads to the destruction of the pathogen
Antibodies are Y shaped proteins that have receptor binding sites that are
Specific to a particular antigen on a pathogen
Antibodies become blind to antigens inactivating the pathogen
This resulting
Antigen-antibody can then be destroyed by phagocytosis
B lymphocytes can respond to antigens on substances that are
Harmless to the body
This hypersensitive response is called an
Allergic reaction.
T lymphocytes role?
There role is to destroy body cells that have been affected by a pathogen
Destruction of infected cells by T lymphocytes
Tea lymphocyte recognises the antigens of the pathogen on the cell membrane of the infected cell
Pt 2
T lymphocytes attached to the infected cell and release proteins
Pt3
These proteins diffuse into the infected cells
4
This causes a cell to produce self-destructive enzymes which causes apoptis AKA programmed cell death
5
The remains of the cellar removed by phagocytosis
T lymphocytes can distinguish between
- Self- antigens on the body’s own cells
- Non-self antigens on infected cells
Failure of the regulation of the immune system leads to
T lymphocytes responding to self antigens
In autoimmunity the T lymphocytes
Attack the body’s own cells
What does this cause
Type 1 diabetes
Rheumatoid arthritis
First exposure of an antigen produced What
A primary response
Some of the cloned B and T lymphocytes
Survive long term as memory cells
When a second exposure to the same antigen occurs these memory cells…
Rapidly give rise to a new clone specific lymphocytes
