Select the correct definition about tissue grafts.
Isografts are between identical twins.
Fever is seldom beneficial because it speeds up the cellular metabolic rate and will not allow antigen-antibody reactions to occur.
Which of the following statements regarding NK cells is a false or incorrect statement?
NK cells are a type of neutrophil.
The mechanism of the "lethal hit" of cytotoxic T cells and NK cells involves a protein called perforin.
B cells respond to the initial antigen challenge by ________.
producing progeny cells that include plasma cells and memory cells
Antigens can be complete or incomplete.
interfere with viral replication within cells
Which of the following statements is incorrect or false?
Class II MHC molecules appear only on the surface of antigen-presenting cells, thymic cells, and T cells that have been activated by exposure to antigens.
Which of the statements below does not describe antigens?
Antigens only come from microbes.
The only T cells that can directly attack and kill other cells are the ________.
Which of the following would be classified as a delayed hypersensitivity reaction?
allergic contact dermatitis
A transfusion reaction is a subacute hypersensitivity to foreign red blood cells.
Small molecules that bind with self-proteins to produce antigenic substances are called ________.
A given pathogen will provoke either a cell-mediated response or an antibody-mediated response but not both.
Select the correct statement about immunodeficiency.
The causative agent in acquired immune deficiency syndrome (AIDS) is a virus that recognizes CD4 proteins.
Complement proteins and antibodies coat a microorganism and provide binding sites, enabling macrophages and neutrophils to phagocytize the organism. This phenomenon is termed ________.
Which of the following is characteristic of complete antigens?
reactivity with an antibody
Innate immune system defenses include ________.
Some immunocompetent cells will never be called to service in our lifetime.
Which of the following is a part of the second line of defense against microorganisms?
Main antibody of both primary and secondary immune response.
Protects mucosal barriers.
Involved in allergies.
Along with IgM, this is a B cell receptor.
Small proteins secreted by virus-containing cells.
Major innate mechanism that mediates destruction of foreign substances in the body.
Stimulate the proliferation of other lymphocytes.
helper t cells
Dampen the activity of both T cells and B cells.
regulatory t cells
Present the double activation signal to T cells.