the humoral response Flashcards
1
Q
describe what is meant by a primary immune response
A
- first time the pathogen has been encountered
- takes time for lymphocytes to create antibodies to destroy pathogens
- symptoms occur
2
Q
what cells are involved in this response?
A
B cells
3
Q
briefly describe the humoral response
A
- T helper cells stimulate B cells by producing interleukins
- initiates a response involving antibodies
4
Q
describe the structure of antibodies
A
- 4 polypeptide chains
- 2 light and 2 heavy
- globular
- quaternary protein
- binding sites are complementary to antigens
5
Q
what is the binding site?
A
a variable region where the antibody and antigen attach
6
Q
state the 3 ways that antibodies work
A
- agglutination
- marking pathogens
- anti toxins
7
Q
what is meant by agglutination?
A
- clumping pathogens
- makes it easier for phagocytes to locate and engulf
8
Q
how do antibodies mark pathogens?
A
- acts as an opsonin
- antibody antigen complex forms
9
Q
how to antibodies act as anti toxins?
A
- binds to toxins
- prevents them entering cells and causing damage
10
Q
stage 1 (clonal selection)
A
- T helper cells bind to B cells with a complementary antibody
- this is clonal selection
11
Q
stage 2 (activation)
A
B cell is activated by the release of T cell interleukins
12
Q
stage 3 (clonal expansion)
A
- B cell divides rapidly by mitosis
- differentiates into plasma or memory cells
- this is clonal expansion
13
Q
stage 4(antibodies)
A
- plasma cells produce antibodies
- antibodies attach to pathogen antigens to destroy them
- by agglutination and marking
14
Q
stage 5 (secondary response)
A
- B memory cells remain in blood after infection
- rapidly produce many antibodies if reinfection occurs
15
Q
define humoral response
A
- humor = body fluids
- takes part in blood plasma and tissue fluid
- as B cells attack pathogens outside cells
