B Lymphocytes And Humoral Response Flashcards
Where are lymphocytes made?
In the bone marrow.
Where do B lymphocytes mature?
In the bone marrow.
What does the humoral response involve?
B cells and antibodies.
Why is it called humoral response?
Antibodies are soluble and transport in bodily fluids which used to be called ‘humour’.
What are antibodies complementary to?
Antigens.
Where do antibodies on a B cell and complementary antigens collide?
In the blood.
Where are antibodies found?
On B cells.
What happens when an antigen and antibody collide?
The B cell takes in the antigen by endocytosis and then presents it on its cell surface membrane.
What happens when an antigen-presenting B cell collides with a helper T cell receptor?
This activates the B cell to go through clonal expansion and differentiation.
How do B cells clone?
They divide by mitosis.
Why do b cells undergo mitosis?
To make large numbers of cells, which differentiate into plasma cells or memory cells.
What do plasma cells make?
Antibodies.
What do memory cells rapidly divide into?
Plasma cells and more memory B cells.
When do memory cells divide?
When they collide with an antigen they have previously encountered.
Why do memory cells divide into plasma cells?
To make large numbers of antibodies and destroy the pathogen rapidly before any symptoms occur.
How long can memory cells live in the blood for?
Decades.
What happens in the first exposure to a pathogen?
The body produces little antibodies at a slow rate.
What happens in the second exposure to a pathogen and why?
The body produces more antibodies at a faster rate as there is a store of memory B cells.
What are antibodies?
A quaternary structure protein with 4 polypeptide chains.
What is agglutination?
Antibodies bind to multiple antigens to clump them together and form an antigen-antibody complex.
How can agglutination occur?
Antibodies are flexible.
Why does agglutination occur?
So phagocytes can easily locate and destroy the pathogens.
