Adaptive Immune System Flashcards
What is an antigen?
Protein expressed by bacteria or virus
What are two types of lymphocytes?
B and T cells
What do B cells do?
Produce antibodies
What happens when B cells detect an antigen?
They divide into plasma and memory cells
What is the primary response?
When antigen contacts the immune system for the first time
What occurs in the secondary response?
Immunological memory is established
What do helper T cells do?
Produces proteins to activate B cells and killer T cells
How are helper T cells activated?
When a phagocyte displays an antigen on its cell membrane
What do killer T cells do?
Attack cells infect by virus
How do killer T cells eliminate infected cells?
They attach them selves to the antigen on the surface and release perforins to induce apoptosis
What kinds of B cells are there?
Helper, memory and standard B cells
What kinds of T cells are there?
Memory, helper and killer T cells
What problems can the adaptive immune system cause?
Rejection of transplant organ, autoimmune diseases, allergic reactions
What do plasma B cells do?
Produce antibodies
How do antibodies help fight infection?
They attach themselves to receptors on pathogen and neutralise it, restrict its movement or prevent it from invading other cells
