MCAT BIO CH. 9 PART 2 Flashcards
What are the three types of immunity?
Innate, humoral and cell-mediated
What is innate immunity?
General nonspecific protection the body provides against various invaders
What is the simplest example of innate immunity?
Skin
Lysozyme examples are in components of innate immunity such as:
Tears, saliva and blood
What is the complement system and what type of immunity is it considered?
A group of 20 blood proteins that can nonspecifically bind to the surface of foreign cells; its an innate immunity
What is humoral immunity?
Specific protection by proteins in the plasma called antibodies (Ab) or Immunoglobulins (Ig)
Each antibody molecule is composed of two copies of two different ______? What are they?
Polypeptides; light chains and heavy chains joined by disulfide bonds
What are the two regions that make up an antibody?
Constant region and variable (antigen binding) region
What are the five main types of immunoglobulins classes?
IgG, IgA, IgM, IgD, and IgE
What is the most antibody circulating in the plasma?
IgG Class
Where is IgM located?
Blood and B cell surface
Where is IgG located?
Blood
Where is IgD located?
B cell surface
Where is IgA located?
Secretions (saliva, mucus, tears, breast milk)
Where is IgE located?
Blood
What is the function IgM?
- Initial immune response
- Pentameric structure in blood
- Monomeric structure on B cell as antigen receptor
What is the function of IgG?
- Involving in ongoing immune response
- Can cross placental barrier
What is the function of IgD?
- Serves with IgM as antigen receptor on B cells
What is the function of IgA?
- Secreted in breast milk
- Helps protect newborns, dimeric structure
What is the function of IgE?
Involved in allergic reactions
What is an antigen?
Molecule an antibody binds to
How is the specificity of antigen binding determined by?
The fit of antigen in a small three-dimensional cleft formed by the variable region of the antibody molecule
What is an epitope?
A small sit on an antigen that an antibody recognizes within a larger molecule
What is a carrier based on antigens?
Small molecules that bound to an antigenic large molecule; the large molecule is considered a carrier