Exam (elaborations) Pathophysiology Biologic Basis for Disease 8th Edition Kathryn L. Mac Cance, Sue E. Huether

Exam (elaborations) Pathophysiology Biologic Basis for Disease 8th Edition Kathryn L. Mac Cance, Sue E. Huether . 1.What is the term for the process during which lymphoid stem cells migrate and change into either immunocompetent T cells or immunocompetent B cells? a. Clonal diversity b. Clonal differentiation c. Clonal selection d. Clonal competence ANS: A The process is called the generation of clonal diversity and occurs in specialized (primary) lymphoid organs—the thymus gland for T cells and the bone marrow for B cells. Clonal differentiation, selection, and competence do not describe this process. 2.What is a role of a natural killer (NK) cells? a. Initiation of the complement cascade b. Elimination of malignant cells c. Binding tightly to antigens d. Proliferation after immunization with antigen ANS: B The main function of NK cells is to recognize and eliminate cells infected with viruses, although they are also somewhat effective at eliminating other abnormal host cells, specifically cancer cells. The complement system is activated in one of three ways (classical, lectin, and alternative), none of which involve NK cells. Antibodies bind tightly to antigens. Immunization leads to the proliferation of antibodies . 3.Which mode of chemical signaling uses local chemical mediators that are quickly taken up, destroyed, or immobilized? a. Paracrine b. Autocrine c. Neurotransmitter d. Hormone ANS: A In paracrine signaling, cells secrete local chemical mediators that are quickly taken up, destroyed, or immobilized. Autocrine signaling occurs when the target cells produce signals that they themselves respond to. Neurotransmitters are released by neurons and cross the synaptic cleft to communicate with the cells they innervate. Hormones are released by one set of cells and travel through tissues or the bloodstream to another set of cells where they produce a response by those cells. 4.Neurotransmitters affect the postsynaptic membrane by binding to which structure? a. Lipids b. Ribosomes c. Amphipathic lipids d. Receptors ANS: D In each type of chemical signaling, the target cell receives the signal by first attaching to its receptors. The other options do not correctly describe this process.