The lymphoid system is composed of all of the following, except
A) the spleen. B) the venae cavae. C) lymphatic vessels. D) lymph. E) lymph nodes.
________ are clusters of lymphoid nodules deep to the epithelial lining of the small intestine.
A) Peyer patches B) Immune complexes C) Lymph glands D) Adenoids E) Tonsils
Each of the following is a physical barrier to infection, except
A) body hair. B) epithelium. C) complement. D) basement membranes. E) secretions.
Defense of the body against a particular pathogen is provided by
A) nonspecific immunity. B) fever. C) skin defenses. D) specific immunity. E) immunological surveillance.
The cells responsible for the production of circulating immunoglobulins are ________ cells.
A) helper T B) NK
C) liver D) plasma E) thymus
The medullary cords of a lymph node contain ________ lymphocytes and plasma cells.
A) B B) medullary C) cordal D) cytotoxic T E) NK
Cells that help regulate the immune response are ________ cells.
A) cytotoxic T B) B C) NK D) plasma E) helper T
Immunoglobulins that are most abundant and are responsible for resistance against many viruses, bacteria, and bacterial toxins are
A) IgA. B) IgD. C) IgG. D) IgM. E) IgE.
Immunoglobulins, formed of five subunits, that are the first antibodies to be produced in response to infection, are
A) IgE. B) IgM. C) IgD. D) IgG. E) IgA.
Which of the following statements about MHC proteins is not true?
A) allow the body to differentiate its own cells from foreign cells B) bind complement C) are found on all nucleated cells
D) fall into two major classes E) function in antigen presentation
Helper T cells do all of the following, except
A) trigger B-cell division, plasma cell maturation, and antibody production. B) attract and stimulate the activity of NK cells. C) provide a rapid response to a future exposure to the antigen. D) enhance nonspecific defenses. E) enhance production of memory and cytotoxic T cells.
The following are steps in the cell-mediated immune response. 1. Several cycles of mitosis occur. 2. Antigen is engulfed and presented by a macrophage. 3. Cytotoxic T cells migrate to focus of infection. 4. T cells with specific receptors recognize the antigen. 5. T cells differentiate into cytotoxic T cells or T memory cells. 6. Cytotoxic T cells release perforin and/or lymphotoxin. The correct sequence for these steps is
A) 1, 2, 4, 5, 3, 6. B) 3, 2, 4, 1, 5, 6. C) 3, 6, 4, 5, 1, 2. D) 4, 1, 5, 3, 6, 2. E) 2, 4, 1, 5, 3, 6.
During a primary humoral response to antigens all of the following occur, except
A) the first immunoglobulins to appear in circulation are of the IgM type. B) B cells may differentiate into plasma cells immediately. C) antibody levels do not peak until 1 to 2 weeks after the initial exposure. D) neutrophils invade the surrounding areas, releasing chemotactic substances. E) B cells may undergo several rounds of mitosis before producing plasma cells and memory cells.
Class II MHC proteins are present in the plasma membrane only
A) during infections. B) when NK cells are activated. C) in antigen-presenting cells and lymphocytes. D) when cytotoxic T cells are inhibited. E) when plasma cells are releasing antibodies.
Histamine increases blood flow and vascular permeability. This would account for all of the following changes that occur during inflammation, except
A) movement of defense proteins and cells into the interstitial space. B) redness of the inflamed tissue. C) chemotaxis of phagocytes. D) heat of the inflamed tissue. E) swelling of the inflamed tissue.