QUESTION 82 Which of the following cells is NOT an APC? O mature B cells Onatural killer cells macrophages O dentritic cells O None of the answers is correct; all of these are APCS. QUESTION 83 Class I and II MHC molecules O consists of a complex of two protein chains and contains alpha-1 and alpha-2 domains that forms an antibody-binding pocket. O contains alpha-1 and alpha-2 domains that forms an antibody-binding pocket. O consists of a complex of two protein chains. O neither consists of a complex of two protein chains nor contains alpha-1 and alpha-2 domains that forms an antibody-binding pocke QUESTION 84 Class II MHC genes code for O all HLA antigens. O certain secreted complement components. O self receptors recognized by natural killer cells. O receptors located primarily on macrophages, dendritic cells, and B cells.

Question 5 Save Answer Several months after the initial vaccination schedule to achieve COVID immunity, the protection against COVID diminishes, and "boosters" are recommended to re-establish full immune protection. What is the part of the immune response that naturally wanes or diminishes during that time so that boosters are needed? a. Levels of circulating antibodies such as lgG decrease because of their usual half-life in the blood. O b. The antigen processing dendrites stop working because they get tired of doing all that hard work and not getting proper recognition and credit. c. Natural killer cells lose their ability to recognize and kill virus-infected cells. d. The memory B-cells lose the ability to remember the SARS-CoV-2 antigens.

QUESTION 22 The tonsils o O filter lymph. help store red blood cells. decrease in size in adults. are made of lymphoid tissue and do not have a capsule

QUESTION 6 Which of the following is a response of our innate defense system? adaptive immunity inflammation cytotoxic T cell response helper T cell response O adaptive immunity inflammation O cytotoxic T cell response O helper T cell response