HMX Immunology Test 2 Questions with 100% Correct Answers | Latest Version 2024 | Verified

T-cell receptors, when coexpressed with CDS mole cules, are restricted to recognizing and binding peptide fragments associated with A. CD3 molecules. B. CD4 molecules. C. MHC class I molecules. D. MHC class II molecules. E. MHC class Ill molecules. - The correct answer is C. cos+ T cells are re stricted to the recognition of pMHC I complexes. C03 molecules are associated with the TCR on the T-cell surface and are found on both mature C04+ and cos+ T cells. C04+ T cells are restricted to the recognition of pMHC class II complexes. MHC class Ill molecules include complement components C4, Bf, and C2 and are not involved in T-cell recognition. B lymphocytes synthesize and express immunoglobulin A. containing multiple epitope specificities. B. in cytoplasmic phagosomes. C. in membrane complexes also containing CD3. D. on their cell membrane surface. E. only after leaving the bone marrow. - The correct answer is D. B cells synthesize and express immunoglobulin on their cell surfaces. Immunoglobulins within an individual B cell contain specificity for one epitope, not several. Cytoplasmic phagosomes are involved in degradation of unwanted materials. Membrane complexes also containing C03 are T-cell receptors (TCR) on the surfaces of T cells. B cells express surface lgM before leaving the bone marrow. The primary lymphoid organs are those in which A. adaptive immune responses are usually initiated. B. filtration devices remove foreign matter.C. large numbers of circulating leukocytes make contact with one another. D. lymphocytes undergo their initial differentiation. E. pattern recognition receptors bind antigens. - The correct answer is D. Primary lymphoid or gans are sites where lymphocytes undergo their initial differentiation. Adaptive immune respons es are initiated by mature lymphocytes that have migrated out of primary lymphoid organs. Secondary lymphoid organs contain filtration devices to remove foreign materials. Circulating leukocytes are found within blood and lymph and secondary lymphoid organs but not within primary lymphoid organs. Pattern recognition receptors (PRRs) are expressed by cells of the innate immune system (see Chapter 5). The thymus is the site of initial differentiation for A. B cells. B. erythrocytes. C. hematopoietic stem cells. D. NK cells. E. T cells. - The correct answer is E. The thymus is the site of initial differentiation of T cells. Eryth rocytes develop from erythroid precursors in the bone marrow. Hematopoietic stem cells differentiate along any one of several lineages within the bone marrow. Natural killer (NK) cells develop within the bone marrow and lack rear ranged TCR. Lymph nodes have two main regions: the A. cortex and medulla. B. lymph and cortex. C. reticulum and cortex. D. lymphandmedulla. E. reticulum and medulla - The correct answer is A. Lymph nodes are di vided into the cortex and the medulla. Lymph is the watery fluid of the lymphatic circulatory sys tem that contains leukocytes and cellular debris from various organs and tissues. Reticulum referstotheframeworkofalymphnodethatis composed of phagocytes and specialized kinds of reticular or dendritic cells. Which of the following molecules is expressed on the