Antibodies

use of hinge region

allow flexibility so antibody can grip to more than 1 antigen

constant regions

allows biding to receptors on immune cells, same for all antibodies

neutralisation

antibodies cover whole pathogen binding site preventing the pathogen from binding to the host cell

what happens when the body is reinfected

antibodies need to be made but due to the memory cells antibodies can be produced quicker and larger quantity

variable regions

complementary shape to a particular antigen, varies between antibodies

bonds holding antibody

disulfide bridges

agglutination

each antibody has 2 binding sites so its able to crosslink pathogens by binding 2 pathogens to one antibody, this prevents the pathogen entering host cell and helps phagocyte engulf it

primary immune response

initial response caused by a first infection

secondary immune response

more rapid and vigorous response caused by a second infection of the same pathogen

what happens to antibodies once pathogen killed

number reduced and they don't stay in blood

4 ways in which antibodies work

opsonins, neutralisation, agglutination, anti toxins

immunoglobins

proteins produced by plasma cells in the immune system

memory cells

recognise specific antigens on pathogen

how do b cells produce different antibodies

slightly different dna

anti toxins

some antibodies bind to molecules that are released by pathogenic cells which are toxic preventing them from harming host cells

why is the primary response longer

takes a few days for the number of antibodies to reach a level that combats an infection successfully as there arent many b cells to make the number of antibodies

antibodies

they are proteins that are specific to the antigen and stimulate an immune response

opsonins

type of antibody that binds to antigens and act as a binding site for phagocytes so they can easily digest the pathogen

structure of antibody (3)

y shaped, 4 polypeptide chains, 2 regions

how do antibodies work

2 binding sites so they can clump together 2 pathogens, phagocytes bind to antibodies and engulf pathogen