unit 2, humoral response and antibodies Flashcards
Where are B lymphocytes made and mature?
bone marrow
Why can B lymphocytes attack only one antigen?
they have specific shape surface receptors to certain antigens, they are complementary
can B lymphocytes attack more than one antigen?
no, they’re millions of different B lymphocytes, they are specific to only ONE antigen
can B lymphocytes bind directly to viruses?
no
When are B cells stimulated?
- viruses present their antigens on their cell surface membrane or on phagocytes
-T helper cells bind to this
-T cells divide by mitosis, helper cells then stimulate b cells to divide and make plasma cells
what are plasma cells clones of?
B cells
if their is no activation of B cells , what is not produced?
antibodies
what is the process for humoral response?
1) invading bacteria enters body
2)bacteria has specific antigens on cell surface membrane
3)correct B cell binds to receptor in the blood, as its specific and complementary to the antigen
4)binding to bacteria activates B cell, T helper cells stimulate the B cell to go through clonal expanison and differentiation (clonal selection)
5) After b cell has divided by mitosis they differentiate into plasma and memory cells
what are memory cells?
-long term, they live for decades
-divide rapidly into plasma cells when reinfected with the same antigen, to make large number of antibodies
-this results in large number of antigens stopping pathogen and its syptoms
what are plasma cells?
secrete large quantities of one antibody, that circulates in the blood
why is the secondary response quicker than the primary response?
There are fewer steps. B memory cells are activated, and divide into plasma cells producing antibodies. t memory cells are activated and stimulate t cells to kill pathogen.
What is the similarities in primary and secondary response?
-both require T cells
-both produce antibodies
What is the differences in primary and secondary response?
-secondary has a faster response
-secondary produces more antibodies and quicker
-secondary uses memory cells
What is the primary response?
A foreign antigen is detected for the first time in the body. The t helper cell binds to this and stimulates b cells to divide by mitosis forming plasma and memory cells to destroy pathogens.
What is the secondary response?
Antigen is detected by T cells. As it has previously been in the body before, the memory cells divide quickly to form plasma cells and more memory cells to replace the ones that have just divided.
