The Immune System Flashcards
What is an antigen?
They are a molecule on the outside is a foreign cell that cause the production of antibodies and the immune response
What is a specific immune system?
Action of a lymphocyte in response to the entry of a foreign antigen to the body
What is a lymphocyte?
White blood cells involved in the specific immune response activated by the presence of a specific antigen which is complementary to receptors on the lymphocyte membrane
What is a macrophage?
Large phagocytes in the tissue and lymph noted that remove foreign materials and act as antigen presenting cells for lymphocytes. It also releases cytokines to B plasma cells
Where are B cells made?
Bone marrow by stem cells differentiating cells
Where are T cells made?
Thymus
Where are B cells made?
Bone marrow by stem cells differentiating cells
What is special about a lymphocytes structure?
Multilobed nucleus
Where are B cells matured?
In the bone marrow
Where are T cells matured?
Thymus
Where are B cells found?
They spread on the body and are found in the lymph nodes and spleen
Where are T cells found?
They circulate in the blood and lymph
What are T helper cells used for?
They release cytokines to stimulate B cell development and stimulate phagocytes to do phagocytosis
What are T killer cells used for?
They attach body cells that display the foreign antigen
What are T regulatory cells used for?
They shut down the immune response once it’s done and they stop the T killer cells from eating the organisms cells
What are T memory cells used for?
They at wised for long term immunity by having the disease’ antigen as the complementary receptor
What are plasma cells?
They circulate in the blood making and releasing at antibodies
What are B memory cells used for?
Stay in the body for a long time so the body remembers the pathogen
How does H.I.V affect the immune response?
It kills the T helper cells so they can’t pass on the messages to the other cells
What is clonal selection
When the antigen and pathogen or antigen presenting cell are complementary to each other causing proliferation. T helper cells can send interleukins to B cells to cause them to have to have clonal expansions. B cells can’t do the other way round.
What is clonal expansion?
This is when the right B and T cell multiplies by mitosis so that it can stop the pathogen
What does a B cell bind to during clonal selection?
They bond directly to the pathogens antigens.
What does a T cell bind to?
It binds to an antigen presenting cell ore the pathogen or an infected cell
What is cell signalling?
This is when different cells communicate to each other
What do macrophages release and their effect?
They can release monokynes to attract neutrophils to come by chemotaxis. They also signal to stimulate B cells to differentiate and release antibodies
What do T cells and macrophages release and their effect?
They release interleukins which can stimulate the clonal expansion so B and T cells differentiate
What is chemotaxis?
It is the movement of chemical towards a certain chemical molecule
How is autoimmune disease cause?
When a hidden antigen in the immune system comes out and is it recognised by the body as notself
If a pathogen has a very similar antigen to a self cell so the self cell is attacked
Give 2 examples of autoimmune diseases?
Lupus
Arthritis
What happens to the concentration of antibodies in the primary response?
There is a small delay then it increases then goes down and eventually becomes 0
What happens to the concentration of antibodies in the secondary response?
It increases more than the primary structure at a faster rate and takes a longer time to decrease and reach a higher peak
What is the initial response?
The first exposure to the pathogen
What is the secondary response?
Second exposure to the same pathogen
Why does the secondary response have a quicker immune response?
There are more B and T memory cells that would detect the pathogen and destroy it before any symptoms appear
What type of response are B cells?
Humoural
What type of response are T cells?
Cell mediated
What is a cell mediated response?
The response is carried out by the cells, such as killing infected cells or regulating other cells
What is a humoural response?
The response is carried out by antigens that aren’t cells
How do T killer cells work?
It
Where can scientists get natural substances to develop new medicines?
Plants
Microorganisms
