Chapter 15: The Immune System

Delayed hypersensitivity is mediated by A. T cells. B. B cells. C. Plasma cells. D. Natural killer cells.

A.

Which of these cell types aids the activation of T lymphocytes by antigens? A. Macrophages B. Neutrophils C. Mast cells D. Natural killer cells

A.

Mast cell secretion during an immediate hypersensitivity reaction is stimulated when antigens combine A. IgG antibodies. B. IgE antibodies. C. IgM antibodies. D. IgA antibodies.

B.

Which of these offers a nonspecific defense against viral infection? A. Antibodies B. Leukotrienes C. Interferon D. Histamine

C.

Which of these statements about class-2 MHC molecules is false? A. They are found on the surface of B lymphocytes. B. They are found on the surface of macrophages. C. They are required for B cell activation by a foreign antigen. D. They are needed for interaction of helper and killer T cells. E. They are presented together with foreign antigens by macrophages.

C.

Active immunity may be produced by A. Contracting a disease. B. Receiving a vaccine. C. Receiving gamma globulin injections. D. Both a and b. E. Both b and c.

D.

Which of the following statements about T lymphocytes is FALSE? A. Some T cells promote the activity of B cells.. B. Some T cells suppress the activity of B cells. C. Some T cells secrete interferon. D. Some T cells produce antibodies.

D.

Which of the following statements about the Fab portion of antibodies is TRUE? A. It binds to antigen. B. It's amino acid sequences are variable. C. It consists of both H and L chains. D. All of the above are true.

D.

Which of the statements about complement proteins C3a and C5a is FALSE? A. They are released during the complement fixation process. B. They stimulate chemotaxis of phagocytic cells. C. They promote the activity of phagocytic cells. D. They produce pores in the victim cell membrane.

D.

Which of these statements about gamma interferon is FALSE? A. It is a polypeptide autocrine regulator. B. It can be produced in response to viral infections. C. It stimulates the immune system to attack infected cells and tumors. D. It is produced by almost all cells in the body.

D.

During the secondary immune response, A. Antibodies are made quickly and in great amounts. B. Antibody production lasts longer than in a primary response. C. Antibodies of the IgG class are produced. D. Lymphocyte clones are beloved to develop. E. All of the above are correct.

E.

Stimulates ACTH secretion.

Interleukin-1

Stimulates formation of Th1 helper T lymphocytes.

Interleukin-12

Stimulates proliferation of killer T lymphocytes.

Interleukin-2

Perforins

Killer T cells

Lysosomal enzymes

Macrophages

Histamine

Mast cells

Antibodies

Plasma cells