cell recognition and the immune system.- 3.2.4 Flashcards
where do b-lymphocytes mature?
the bone marrow.
what is an antigen?
-part of an organism that is recognised as non self (specific tertiary structure) by the immune system and stimulates a response.
where do t-lymphocytes mature?
thymus .
phagocytes and lymphocytes are involved in destroying microorganisms. Describe how ?
-Antigens engulf the pathogen
-Enclosed in a vacoule.
-Lysosomes have enzymes that hydrolyse the pathogen.
what are the types of lymphocytes
B-lymphocytes
T-lymphocytes
what is a b lymphocyte
involved in humoral immunity
(antibodies that are present in bodily fluids)
what is a t-lymphocyte?
associated with cell mediated immunity.
where are b-lymphocytes made?
-bone marrow
where are t-lymphocytes made
bone marrow
what is the first stage of cell mediated immunity
-invaded PATHOGENS are ingested and digested by MACROPHAGES.
-antigens on the cell surface membrane of the pathogen are DISPLAYED on the CSM of the macrophage.
what is the second stage of cell mediated immunity?
receptors on certain T-Helpers fit exactly onto displayed antigens
what s the third stage of cell mediated immunity
the attachment allows for T-cells to divide rapidly by MITOSIS.
-forming a clone of genetically identical cell.
what can T-cells do?
-activate cytotoxic T-cells.
what do T-cells stimulate?
B-cells allowing it to divide and secrete their antibody.
what can T-cells develop into?
-memory cells that enable rapid responses to future infections by the same pathogens.
why do T-cells stimulate pathgocytes
-in order to engulf pathogens by phagocytosis.
what do to cytotoxic T-cells do?
kill abnormal body cells
& body cells infected by pathogen #
by producing a protein.
what is the protein produced by cytotoxic T-cells?
perforin
what does perforin do?
make holes/pores in the cell surface membrane of pathogen.
-it becomes fully permeable.
where are the antigens found in response to b-lymphocytes
-humoral
-in the blood stream.
what is the process in which an anitgen enters a b-cell
endocytosis.
what happens when an antigen enters the bloodstream
the B-cell with complimentary antibodies attaches to antigen.
what does the t-helper cell do in response to a b-cell binding onto the antigen.
-binds to antigen
-stimulates b-cells to divide—> mitosis
= clones of identical b-cells.
what do b-cells difrentiate into?
-plasma cells
-memory cells
what do plasma cells make?
antibodies
what is the life span of plasma cells?
-short life span.
plasma cell rapidly produce antibodies, TRUE or FALSE
TRUE
what do memory cells divide into?
(mitosis)
-plasma cells
-memory cells
what is the life span of memory cells ?
can last for many decades.
why are memory cells essential in secondary immune responses?
-an increased quantity of antibodies secreted at a faster rate.
what is phagocytosis?
-subsequent destruction of ingested pathogens by lysozymes.
what evidence shows that an antibody has a quaternary structure?
-has multiple polypeptide chains.
explain why the antibody will only detect the antigen?
-specific sequence of amino acids in variable region
-specific tertiary structure.
-therefore is only complimentary to one type of antigen.
what is the first stage of ELISA testing
add antigen to well
what happens when the serum is added to the well
(ELISA testing)
the monoclonal antibodies will bind to antigen.
when the monoclonal antibody is produced what can we depict from that?
(ElSA)
-the disease is present in the body.
(we dont know yet)
why is the well washed?
to remove antibodies that havent binded
why is an enzyme linked anti-HSG bined to the first antibody
-it allows for a colourless substrate to be added
-in order to produce products.
what happens when a product is produced?
-a visible colour change.
-showing tested positive
what is the first process of phagocytosis
white blood cell detects the pathogen because of antigen.
-the antibodies bind onto the antigen.
what is the second process of phagocytosis
endocytosis occurs and the pathogen is engulfed.
what is created when the pathogen is engulfed?
phagocytotic vacoule
what happens when the phagocytic vacoule is created?
the lysosomes fuses with the vacoule
what do the lysozymes do to the vacoule
it hydrolyses it with its enzymes.
what happens after the vacoule is hydrolysed
antigens are presented on the CSM of the WBC.
which triggers an immune response.
