T cells that react with self antigens are destroyed through: A. cytokinesis b. macrophages c. perforins d. apoptosis

Explain why each choice (a-d) is correct or incorrect.  In order for an antigen to activate or sensitize a T helper cell, the antigen must be a. coated with antibodies b. displayed on the surface of an APC along with MHC antigens c. displayed on the surface of another T cell with IgD antibodies d. partly digested by a natural killer cell

Which of following is not a type of T lymphocyte? a. Helper T cell b. Memory T cell c. Cytotoxic T cell d. Mast T cell

Which of the following is TRUE regarding Gram negative bacteria? a- Their cell wall is composed of a large proportion of sugars b- Their cell wall does not absorb the Gram stain and turns pink c- Their cell wall is composed of a small proportion of peptidoglycan d- Two of the above statements are true Which T-lymphocytes activate the B-cell response? 1- suppressor T-cells. 2- cytotoxic T-cells. 3- helper T-cells. 4- memory T-cells. Substances that are injected containing an antigen to stimulate the immune system to respond are called a- antibodies b- medications. c- vaccines d- antibiotics

For an autoimmune disease to occur, lymphocytes do not learn how to recognize foreign pathogens as dangerous and self-antigens as safe. What is the second thing that needs to happen specifically with lymphocytes to have an autoimmune disease? O a. Malfunctioning lymphocytes attach to macrophages O b. Malfunctioning lymphocytes are not destroyed by the body O c. Malfunctioning lymphocytes prevent normal lymphocytes from reproducing O d. Malfunctioning lymphocytes trigger the complement system to initiate an immune response

Any aspect of the immune system can be deficient.  Which of the following deficiencies would primarily affect the BARRIER function of immunity? Group of answer choices A. Complement Deficiencies, in which a variety of complement proteins do     not  function properly B. DiGeorge Syndrome, in which the thymus does not develop properly C. Selective IgA deficiency, in which IgA antibodies are produced in very low amounts D. Severe Combined Immune Deficiency (SCID), in which all T and B cell functions are absent

Explain why each choice (a-d) is correct or incorrect.  Which statement is true about T cells? a. They usually directly recognize antigens, which then activates a subpopulation of killer cells b. Their proliferation is enhanced by interleukins 1 and 2. c. Once activated, they cannot secrete cytokines. d. They will develop into cytotoxic T cells if antigen is complexed with class II MHC proteins.

Which of the following pairs is mismatched? a. plasma cell: mediation of phagocytosis and killing of microorganisms in the plasma b. megakaryocyte: formation of platelets c. dendritic cell: activation of adaptive immune responses d. natural killer cell: develops from a common lymphoid progenitor e. neutrophil: formation of pus f. regulatory T cell: inhibition of T-cell activity.