Ch.15

Question 1

What are antibodies and how do they help protect against invading pathogens? (make sure you include antigens in your explanation)

Answer 1

• (immunoglobulins) have Y-shaped structure called an antibody monomer
• Antibodies bind to antigens on invading pathogens like bacteria and viruses to mark them for destruction by other immune cells, thus protecting the body from infection

Question 2

What is an epitope?

Answer 2

the part of an antigen that an antibody attaches to

Question 3

Where do T cells mature vs where do B cells mature?

Answer 3

• T cells muture in thymus
• B cells mature in bone marrow

Question 4

What is another name of a T helper cell?

Answer 4

• have a CD4 marker

Question 5

What is another name for a T cytotoxic cell?

Answer 5

• “corrupt” host cells
• have CD8 marker

Question 6

What are the 2 types of antigen presenting cells? What does it mean to be an antigen presenting cell? Who do they present antigens to?

Answer 6

• dendritic cells and macrophages
  – present antigens to T cells
• Antigen must be presented by another host cell

Question 7

What are MHC class I molecules? (Who has them and what is their function?)

Answer 7

• Cytotoxic T cells only recognize antigens presented on MHC class I
• MHC class I molecules present antigens made by self cell (endogenous antigens)

Question 8

What are MHC class II molecules? (Who has them and what is their function?)

Answer 8

• Helper T cells have CD4 marker and only recognize antigens presented on MHC class II
• MHC class II molecules present antigens taken up by the self cell from its environment (exogenous antigens)

Question 9

Another term for antibody is immunoglobulin. How is an immunoglobulin monomer built (What are it’s two parts?)

Answer 9

• Fab region: two identical arms that bind antigen
• Fc region: stem that serves as a “red flag” that sticks out from the surface of an antibody-bound antigen and marks it for elimination by macrophages
• Variable region at the end of each arm and binds to the antigen
• constant region is closest to the cell surface

Question 10

How many classes of antibodies are there?

Answer 10

5: IgA, IgD, IgE, IgG, IgM,

Question 11

Each class of antibody (immunoglobulin) is specifically defined by region. Which region is this (how do we tell the different types of antibodies apart?)

Answer 11

Each class has different constant region of heavy chain

Question 12

There are billions of types of antibodies yet only about 80K – 100k genes. How does our body produce so many different types of antibodies?

Answer 12

Gene rearrangement generates diversity

Question 13

Which type of B cell secretes antibodies?

Answer 13

plasma cells

Question 14

What are giant cells?

Answer 14

Activated macrophages fused together