A researcher finds that some of her mice lack appropriate B cell function; they seem unresponsive to antigens that should stimulate B cells. She discovers that although these mice produce healthy B cells and normal-looking receptors, those receptors are only present within B cells rather than on the B-cell surface. The researcher concludes that these cells are lacking which of the following?

MCQs on the immune system, including innate and adaptive immunity, the cells involved in each of process of the immune system and their role in the immune response, and how antibodies are used to confer immunity for future potential exposures.