study guide adaptive immunity Flashcards
(37 cards)
● is the body’s specific defense mechanism that involves the recognition and targeted response to pathogens.
Adaptive immunity
adaptive immunity has two specific characteristics
specificity
memory
Targets specific antigens.
specificity
Provides quicker and stronger responses upon subsequent exposures to the same antigen.
memory
lymphocytes
B cells
T cells
mediate humoral immunity (antibody production)
B cells
mediate cell mediated immunity
T cells
molecules that elicit an immune response○ Can be proteins, polysaccharides, or other macromolecules on the pathogen surface..
antigens
○ Include dendritic cells, macrophages, and B cells.
○ Capture antigens and present them to T cells using Major Histocompatibility Complex (MHC) molecules.
APCs antigen presenting cells
○ Involves B cells and the production of antibodies.
humoral immunity
Occurs when B cells bind to specific antigens and receive help from helper T cells.
Activation of B cells
Clonal selection: Activated B cells proliferate and differentiate into:
plasma and memory B cells
secrete antibodies
plasma cells
provide long term immunity
memory B cells
Coordinate immune responses by releasing cytokines.
Helper T cells (CD4+):
Kill infected or cancerous cells.
- Cytotoxic T cells (CD8+):
Antigens presented by MHC class I molecules activate
cytotoxic T cells
- Cytotoxic T cells destroy infected cells by releasing
perforins and granzymes.
The initial exposure to an antigen leads to a slower and weaker response.
Primary response:
○Subsequent exposures result in a rapid and robust response due to memory cells.
Secondary response:
produced by plasma cells
antibodies
binds to specific antigens
variable region
determines the antibody class
constant region
classes of antibodies
IgG, IgA, IgM, IgE, IgD