41. Immune System

Which of the following cell types carries out humoral immunity?

Which of the following functions of plasma-cell-secreted antibodies promotes phagocytosis of foreign bacteria?

The proliferation of the B lymphocyte to which a specific antigen binds is referred to as __________.

Once you have been exposed to an antigen, you develop immunity against the same antigen because __________.

The antigen-binding sites of an antibody molecule are formed from the molecule's variable regions. Why are these regions described as variable?

The body produces antibodies complementary to foreign antigens. The process by which the body comes up with the correct antibodies to a specific invader is most like __________.

A viral infection in a cell results in __________.

What is the primary difference between the innate and adaptive immune responses?a. The innate immune response does not distinguish between pathogens, while the adaptive immune response does.b. Only the innate immune response is activated by antigens.c. The adaptive immune response generates immunological memory and is more specific than the innate immune response.d. The innate immune response does not kill cells; the adaptive immune response does.

An epitope associates with which part of an antigen receptor or antibody?a. the tailb. the heavy-chain constant regions onlyc. variable regions of a heavy chain and light chain combinedd. the light-chain constant regions only

Which statement best describes the difference between responses of effector B cells (plasma cells) and those of cytotoxic T cells?a. B cells confer active immunity; cytotoxic T cells confer passive immunity.b. B cells respond the first time a pathogen is present; cytotoxic T cells respond subsequent times.c. B cells secrete antibodies against a pathogen; cytotoxic T cells kill pathogen-infected host cells.d. B cells carry out the cell-mediated response; cytotoxic T cells carry out the humoral response.

Which of the following statements is true?(A) An antibody has one antigen-binding site. (B) A lymphocyte has receptors for a single antigen. (C) Every antigen has a single epitope. (D) A liver or muscle cell makes two classes of MHC molecule

Which of the following best describes the difference in the way B cells and cytotoxic T cells deal with invaders?a. B cells confer active immunity; T cells confer passive immunity.b. B cells send out antibodies to attack; certain T cells can do the attacking themselves.c. T cells handle the primary immune response; B cells handle the secondary response.d. B cells are responsible for the cell-mediated immune response; T cells are responsible for the humoral immune response.

What is one of the differences between CD4+ and CD8+ T cells?a. CD4+ cells are immature, and CD8+ cells are mature.b. CD4+ cells are activated, and CD8+ cells are not.c. CD4+ cells interact with class II MHC proteins, and CD8+ cells interact with class I MHC proteins.d. CD4+ cells activate cell-mediated responses, and CD8+ cells activate humoral responses.

Which of the following should be the same in identical twins?a. the set of antibodies producedb. the set of MHC molecules producedc. the set of T cell antigen receptors producedd. the set of immune cells eliminated as self-reactive

Cytotoxic T cells are able to recognize infected body cells becausea. the infected cells display foreign antigens.b. the infected cells produce antigens.c. infected cells release antibodies into the blood.d. helper T cells destroy them first.