Quiz

QUIZ

1. What statement is not true of B lymphocytes or B cells?

a. Mature B cells are called plasma cells. b. These cells make antibodies. c. The cells mature in the bone marrow. d. These cells are not directly associated with memory.

Answer: d. Each of these is true of the B cells except they are directly associated with memory. There are memory B cells that retain the ability to make antibodies to a subsequent infection.

2. What is the difference between PAMPs and antigens?

a. Antigens are not related to pathogens and PAMPs are related to pathogens. b. Antigens are specific to a particular pathogen and PAMPs are not specific. c. Antigens are made from glycoproteins and PAMPs are lipids. d. Antigens are associated with viruses and PAMPs are associated with bacteria.

Answer: b. Antigens and PAMPs are very similar except that PAMPs are not specific to a particular pathogen, while antigens are very specific to a pathogen.

3. What structure is least likely to be an antigen?

a. Viral spike protein b. Bacterial capsule c. Nucleic acid segment d. Fimbriae components

Answer: c. Antigens tend to be something on the outside of a virus, bacterium, or other pathogen but nucleic acids, being internal, are not generally antigenic.

4. Which type of antibody is the most abundant antibody and is the only one that crosses the placenta?

a. IgM b. IgG c. IgE d. IgA

Answer: b. IgG makes up 80 percent of antibodies and is the only antibody that directly crosses the placenta in order to provide passive immunity to the fetus.

5. Which type of antibody is found in mucus and mucous membranes so that it can trap pathogens there?

a. IgG b. IgE c. IgA d. IgM

Answer: c. IgA is predominantly found in the mucous membranes and in mucus, where it traps pathogens before they can get into the body tissues themselves.

6. Which antibody has the best ability to agglutinate pathogens because it has ten Fab regions together involved in its structure for binding to antigens?

a. IgG b. IgE c. IgA d. IgM

Answer: d. IgM is pentameric, meaning that it has ten Fab regions. This makes it the best antibody for agglutination of pathogens, which can more easily be phagocytized.

7. What type of molecule is a major histocompatibility complex molecule?

a. Nucleic acid b. Glycoprotein c. Lipid d. Carbohydrate

Answer: b. The MHC molecules are glycoproteins that span the membrane of the cells they exist on. Their role is to be recognizable as self-antigens.

8. Where does the selection of T cells happen?

a. Bone marrow b. Lymph nodes c. Thymus d. Peripheral tissues

Answer: c. The selection of T cells to be used for the immune system happens in the thymus, which has a cortex and a medulla for these processes.

9. Which type of cell is involved with peripheral tolerance because they help to deactivate self-reacting T cells?

a. Memory T cells b. Cytotoxic T cells c. Immature thymocytes d. Regulatory T cells

Answer: d. Regulatory T cells participate in peripheral tolerance by getting rid of self-activating T cells that would otherwise cause an autoimmune reaction to self-cells.

10. Which cell type of the adaptive immune system is most closely related to NK cells in terms of what they can do?

a. CD4 cells b. CD8 cells c. Memory T cells d. Regulatory T cells

Answer: b. CD8 cells are called cytotoxic T cells. They are activated by specific infected cells and kill them in similar ways as NK cells do.