Immuno Set 1 Flashcards
In DiGeorge syndrome, the thymus fails to develop. Which of the following characterizes the immunodeficiency state in this syndrome?
A. Deficiency in monocytes and tissue macrophages
B. Defect in naive B cell activation and antibody production in response to bacterial polysaccharides
C. Deficiency in T lymphocytes and associated defects in cell-mediated immunity
D. Normal numbers of naive T cells that cannot be activated by antigen
E. Deficiency in B cell maturation
C. Deficiency in T lymphocytes and associated defects in cell-mediated immunity
According to the clonal selection hypothesis, which of the following is correct?
A. Lymphocyte specificity is determined by exposure to an antigen
B. Clones of lymphocytes specific for antigens develop prior to exposure to the antigens
C. Antigen binding to a lymphocyte receptor selects that lymphocyte to die
D. Antigen binding to secreted antibody stimulates proliferation of the B cell that secreted the antibody
E. Each clone of lymphocytes express receptors for many different antigens
B. Clones of lymphocytes specific for antigens develop prior to exposure to the antigens
Lymphoid lineage cells
A. are the most numerous leukocyte population.
B. consist of B, T, and NK cells.
C. contain conspicuous cytoplasmic granules.
D. differentiate from myeloid cell precursors.
E. phagocytize debris and foreign cells.
B. consist of B, T, and NK cells.
Three days ago, an otherwise healthy 17-year-oldboy sustained a skin laceration during a lacrosse match. Yesterday, he complained of mild “flulike” symptoms. This morning, he became suddenly ill with a fever, general muscle aches, and dizziness; then he lost consciousness. On arrival in the emergency department, he had a temperature of 100.8°F and a heart rate of 136 beats per minute. His blood leukocyte count was 22,000 cells per mcL (reference range: 4,500 to 12,500 per mcL). Which type of immune cells are expected to be predominant in the blood of this patient?
A. B lymphocytes. B. juvenile and mature neutrophils C. monocytes and macrophages D. natural killer cells E. T lymphocytes
B. juvenile and mature neutrophils
A subset of which of the following of these undergoes further differentiation within the thymus? A. Basophils B. Eosinophils C. Lymphocytes D. Monocytes E. Neutrophils
C. Lymphocytes
Which of the following cells are important effector cells in allergic reactions?
A. Basophils B. Dendritic cells C. Lymphocytes D. Monocytes E. Neutrophils
A. Basophils
A 16-year-old boy has an acute appendicitis (infection of the appendix). Which of the following blood cells is most likely to increase in number as a result of his condition?
A. Basophils B. Eosinophils C. Lymphocytes D. Monocytes E. Neutrophils
E. Neutrophils
Natural killer cells are members of which of the following families of leukocytes?
A. Basophils B. Eosinophils C. Lymphocytes D. Monocytes E. Neutrophils
C. Lymphocytes
Which of the following statements is consistent with the process of clonal selection?
A. The specificity of a lymphocyte antigen receptor changes to accommodate the structure of an antigen that binds to it.
B. Many different antigen receptors with different specificities are expressed on each lymphocyte.
C. Lymphocytes do not express antigen receptors on their cell surfaces until after exposure to antigen.
D. The diversity of the lymphocyte repertoire for antigens is very small before exposure to antigen but increases significantly after antigen exposure.
E. The diversity of the lymphocyte repertoire for antigens is very large before exposure to antigen, with millions of different clones of lymphocytes, each having a different specificity.
E. The diversity of the lymphocyte repertoire for antigens is very large before exposure to antigen, with millions of different clones of lymphocytes, each having a different specificity.
Which of the following best describes clonal expansion in adaptive immune responses?
A. Increased number of different lymphocyte clones, each clone specific for a different antigen during the course of an infection
B. Increased number of different lymphocyte clones, each clone specific for a different antigen during development of the immune system, before exposure to antigen
C. Increased number of lymphocytes with identical specificities, all derived from a single lymphocyte due to nonspecific stimuli from the innate immune system
D. Increased number of lymphocytes with identical specificities, all derived from a single lymphocyte stimulated by a single antigen
E. Increased size of the lymphocytes of a single clone due to antigen-induced activation of the cells
D. Increased number of lymphocytes with identical specificities, all derived from a single lymphocyte stimulated by a single antigen
In addition to T cells, which cell type is required for initiation of all T cell–mediated immune responses?
A. Effector cells B. Memory cells C. Natural killer cells D. Antigen-presenting cells E. B lymphocytes
D. Antigen-presenting cells
Which of the following properties is common to macrophages and neutrophils?
A. life span B. anatomical location C. ability to phagocytose D. morphology E. formation of pus
C. ability to phagocytose
Which of the following functions is associated primarily with neutrophils?
A. Acute response to bacteria and necrotic tissue B. Chronic inflammatory response C. Responses to viral infections D. Initiating anaphylactic reactions E. Generation of immunological memory
A. Acute response to bacteria and necrotic tissue
Mast cells and basophils differ from each other in which of the following characteristics?
A. Inflammatory mediators are found in their granules
B. The immunologic reactions they participate
C. Their location
D. Their ability to synthesize lipid mediators
C. Their location
Which of the following is NOT part of the innate immune response to extracellular bacteria?
A. Alternative pathway of complement activation
B. Lectin pathway of complement activation
C. Activation of phagocytes by Toll-like receptors
D. Natural killer cell activation
E. Inflammation
D. Natural killer cell activation
