Chapter 12.6 Flashcards
(33 cards)
How does antibiotics defend the body?
- Antibody of the antigen-antibody complex acts as the opsonin so the complex can be easily engulfed and digested by phagocytes
- Most pathogens can no longer effectively invaded the host cells once they are part of antigen-antibody complex
- Antibodies act as acclutinins causing pathogens carrying antigen-antibody complexes to clump together.
- Helping them prevent them spreading through the body and makes it easier for phagocytes to engulf a number of pathogens at the same time. - Antibodies act as an anti-toxin, binding the toxins produced by pathogens and making them harmless.
What are the main type of B lymphocytes?
Plasma Cells
B effector cells
B memory cells
What is the structure of the Antibodies?
- They are Y shaped gycoproteins called immunoglobulins
- Made up of two identical long polypeptide chains that are called heavy chains and two much shorter identical chains called light chains
- Chains are held together by disulfide bridges and they are disulfide bridges within the polypeptide chains holding them together
- Have a binding site area (known as variable region) of 110 amino acids on both heavy and the light chain
- They have a constant region were antibody molecule is the same
What are antigens?
Are molecules on the cell on their surfaces
What are the two types of antigen? What are the differences?
Self antigens - are part of their own cells
Non-self antigens - on the cell of the cells of the pathogen
What is variable region?
The binding site is an area of 110 amino acids on both heavy and the light chains
What is a constant region?
Is the rest of molecule is always the same so it is.
What is antigen-antibody complex?
When an antibody binds to the antigen
What are the types of T-lymphocytes?
T - helper cells
T - killer cells
T - memory cells
T - regulator cells
What is the function of T-Killer cells?
The destroy the pathogen carrying the antigen
How do T-Killer cells work?
They produce a chemical called perforin which kills the pathogen by making holes in the cell membrane so it is freely permeable
How do T regulator cells work?
They stop the immune response once a pathogen has been eliminated and make sure that the body recognises self antigens and does not set up an autoimmune system.
{Interleukin are important for the control}
What is the function of T regulator cells?
responsible for suppressing the immune system acting controlling and regulating
How does T helper cells work?
They have CD4 receptors on their cell surface membranes which hold the surface antigens on the APCs.
The T helper cells produce the interlukins, which then:
- This stimulates the activity the of the B cells which increases the antibody production
- Stimulates the other types of T cells and attract and stimulate macrophages to ingest pathogens with antigen-antibody complexes.
How do T-memory cells work?
When they meet an antigen the second time, they divide rapidly to form a huge number of clone T killer cells that destroy pathogen
What are T memory cells function?
Are part of the immunological response
What is the function of Plasma cells?
They are responsible for producing antibodies to a particular antigen and release them into circulation
What are the function of B effector cells?
responsible for dividing itself to form clone plasma cells.
What are the function of B memory cells?
- They are part of the immunological memory
- They are programmed to remember a specific antigen and enable the body to make a very rapid response when antigen is encountered again
What are lymphocyte?
Are white blood cells
Where are B lymphocyte made/found?
They mature in the bone marrow
Where are T lymphocyte made/found?
They are found in the Thymus Gland
How does Humoral immunity work?
- Activated T helper cells bind to the B cell APC known as clonal selection
- Interleukin then produced by activated T helper cells that activate the B cells
- Activated B cells then divide by mitosis to give clones of plasma cells and Clonal expansion occurs
- Cloned plasma cells then produce antibodies that fit the antigens on the surface of the pathogen - which bind to the antigens and disables them (known as primary response)
- Some cloned B cells develop into memory cells - so if the body is infected again by the same pathogen. B memory cells divide rapidly to form plasma cell clones
{ These then produce the right antibody and wipe the pathogen very quickly}. This is known as secondary immune system
How does cell-mediated immunity work?
- Macrophages engulf and digest pathogens in phagocytosis. They then process the antigens from the surface of the pathgen to form antigen presenting cells (APCs)
- The receptors on some of the T helper cells fit the antigens. The T helper cells become activated and produce interlukins which stimulate more T cells to divide rapidly by mitosis.
They then form clones of identical activated T helper cells that carry the right antigen to bind to a particular pathogen - Cloned T cells may:
- develop into T killer cells and destroyed infected cells.
- produce interleukins that stimulate B cells to divide.
- produce interleukins that stimulates phagocytes.
- develop into T memory cells
