communicable diseases Flashcards
what is part of the bottom of the antibody
receptor binding site
contstant region
what is the part of the top of the antibody
variable region
antigen binding sites
what are the components of a antibody
made of 2 identical polypeptide chains heavy chain light chain and a hinge region where it bends has disulfide bridges between the polypeptide chain holding them in shape
what is another name for antibodies
immunuglobulins
which bind to antigen on the pathegon or toxin
after antibody binds to antigen it forms an antihen-antibody complex
how to antibodies defend the body (3)
1) . Antigen-antibody complex acts as an opsonin so it is easily engulfed by phagocytes
2) . antibodies act as agglutinins causing pathogens carrying antigen clump together to the antigen
3) .antibodies can act as anti toxins binding to the toxins produced by pathogens and making them harmless
name 4 T-lymphocytes and what they do
1) . T helper cells - produce interleukin(cell signalling molecule), stimulate the activity of the B cells , increase antibody production
2) . T killer cells - destroys pathogen carrying the antigen, produce which kills the pathogen by making holes in the cell membrane
3) . T memory cells - live for a long time and are part of the immunological memory if they meet an antigen the 2nd time, they divide rapidly to form a huge number of T killer cells
4) . T regulator cells - suppress the immune system, they stop the immune response once a pathogen has been eliminated so it does not set up an autoimmune response
name 3 B-lymphocytes
1) . plasma cells- produce antibodies to a particular antigen, live for a few days produce 2000 antibodies per second
2) . B memory cells - live for a long time and provide immunological memory remember specific antigen to make a rapid response
3) . B effector cells- these divide to from the plasma cell clones
describe the stages and how phagocytosis works (5)
1). pathogons produce chemicals that attract phagocytes
2) phagocytes recognise non-human proteins on the pathogen
3). the phagocyte engulf the pathogen and encloses it in a vacuole called a phagosome
4). the phagosome combines with a lysosome to form a phagolysosome
5) enzymes from the lysosome digest and destroy the pathegon
after this
macrophages digests the pathogen, antigen comined with major hisocompatability complex (MHC)
antigen moved to surface membrane becoming antigen- presenting cell (APC)
name 2 helpful chemicals and what do they do
cytokines - act as cell-signalling molecules informing other phagocytes that the body is under attack to move them into the site of infection or inflammation
opsonins - bind to the pathogen and tag them so they are easily recognised by phagocytes
what are the 2 types of opsonins
immunoglobulin G
immunoglobulin M
describe how cell-mediated immunity works
- macrophage engulf and digest pathogen; process antigen to become APCs
- T helper cells receptors fit antigen; become activated and produce interleukin’s to stimulate more T cells to divide by mitosis (cloning)
CLONED T CELLS: - develop into T memory cells
- develop into T killer cells
- produce interleukins that stimulate phagocytosis
- produce interleukins that stimulate B cells to divide
describe and explain how humoral immunity work
- Activated T helper cells bind to the B cell APC with the correct antibody
- activated T helper cells produce interleukin’s to activate B cells
- activated B cell divides by mitosis to give clones of plasma cells and B memory cells - clonal expansion
- closed plasma cells produce antibodies that fit the antigens or act as agglutinins primary immune
- some cloned B cells develop into B memory cells
name 3 direct transmission ways of disease transmitting
- direct contact
- inoculation
- ingestion
how are diseases transmitted from direct contact
- kissing or any contact with the body fluids of another person
- direct skin to skin contact (athletes foot)
- microorganisms from faeces transmitted on the hands
how are diseases transmitted from inoculation
- through a break in the skin
- animal bite
- puncture wound or sharing needles
