21. The Immune System

Mark the following statements as true or false. If a statement is false, correct it to make a true statement.

The immune response to a viral infection involves NK cells and different kinds of lymphocytes.

CD4 markers are associated with

(a) Cytotoxic T cells

(b) Regulatory T cells

(c) Helper T cells

(d) All of these

What is the importance of the variable region of T-cell receptors?

Type I hypersensitivity is due to release of inflammatory mediators from_____, and type IV hypersensitivity is due to the actions of_____.

a. T_H cells; macrophages

b. neutrophils; T_H cells

c. B cells; T_C cells

d. mast cells; T_H cells

Lymphocytes that develop immunocompetence in the bone marrow are:

a. T lymphocytes

b. B lymphocytes

c. NK cells

d. B and T lymphocytes

Which of the following is NOT a component of TCRs?

Which of the following statements about cytotoxic T cells is true?

Mark the following statements as true or false. If a statement is false, correct it to make a true statement.

Cancer cells are destroyed by NK cells, T_C cells, and macrophages.

Give a function for each of the following:

(a) Cytotoxic T cells

(b) Helper T cells

(c) Regulatory T cells

(d) Plasma cells

(e) NK cells

Define immunocompetence and self-tolerance. How is self-tolerance achieved?

Mark the following statements as true or false. If a statement is false, correct it to make a true statement.

Dendritic cells may activate both T_H and T_C cells.