IMMUNODEFICIENCY Flashcards
Two major kinds of defense have evolved that counter threats:
–________ immunity and _______ immunity
Innate; acquired
Innate immunity
– Is present _______________ and is effective from ____________
– Involves (specific or nonspecific?) responses to pathogens
before any exposure to pathogens
the time of birth
nonspecific
Acquired immunity, also called ______ immunity
– Develops only after ____________________ such as microbes, toxins, or other foreign substances
– Involves a ( specific or non-specific ?) response to pathogens
adaptive
exposure to inducing agents
very specific
Natural Killer Cells
Natural killer (NK) cells
– Patrol the body and attack ______-infected body cells and _____ cells
– Trigger ______ in the cells they attack
virus; cancer
apoptosis
The lymphatic system
– Plays a/an (active or passive?) role in defending the body from pathogens
Active
In acquired immunity, ________ provide specific defenses against infection
Acquired immunity
– Is the body’s ______ major kind of defense
– Involves the activity of ___________
lymphocytes
second
lymphocytes
An antigen is any foreign molecule
•That is specifically recognized by _________ and ______________
lymphocytes; elicits a response from them
A lymphocyte actually recognizes and binds
•To just a small, accessible portion of the antigen called an _______
epitope
Antigen Recognition by Lymphocytes
Two main types of lymphocytes
– B lymphocytes (B cells) and T lymphocytes Which circulate through the blood
The plasma membranes of both B cells and T cells
– Have about _______ antigen receptor that all recognize the same epitope
100,000
B Cell Receptors for Antigens
B cell receptors
Bind to (specific or non-specific?) , intact antigens
Are often called _________ or ___________
Specific
membrane antibodies or membrane immunoglobulins
B lymphocytes or B cells produce _______ involved in ______ immunity.
B cells are produced in the _______, where the initial stages of maturation occur, and travel to the _____ for final steps of maturation into __________ B cells.
antibodies; humoral
bone marrow; spleen
naive mature
B-cells are activated by the binding of ______ to ______ on its cell surface which causes the cell to divide and proliferate.
Some stimulated B-cells become ______ cells, which secrete _______.
Others become ____-lived ____ B-cells which can be stimulated at a later time to differentiate into plasma cells
antigen; receptors
plasma; antibodies
long; memory
Somatic hypermutation is a process that allows ____ cells to _________ that they use to produce antibodies.
This enables the B cells to _________ that are better able to _______ bacteria, viruses and other infections
B; mutate the genes
produce antibodies
bind to
Somatic hypermutation occurs in T- cell receptor genes
T/F
F
Somatic hypermutation does not occur in T- cell receptor genesh
Each T cell receptor
– Consists of ______ different polypeptide chains
two
T cells bind to (small or long?) fragments of antigens That are bound to normal cell-surface proteins called ______ molecules
Small
MHC
MHC molecules
MHC molecules
Are encoded by a family of genes called the ______________
major histocompatibility complex
Infected cells produce MHC molecules
– Which bind to _____________ and then are transported to the ______ in a process called __________
antigen fragments
Cell surface
antigen presentation
There are three types of antigen presenting cells in the body: __________,__________,__________ .
macrophages, dendritic cells and В cells
After antigen presentation :
A nearby T cell
– Can then detect the _______ displayed on the _______ of APC
antigen fragment
cell’s surface
Peptide antigens are handled by (the same or different?) classes of MHC molecules
Different
