Which of the following is the first event in defense against bacteria
A)interferon release
B)antigen appearance on plasmalemma
C)activation of B cells
D)activation of T cytotoxic cells
E)macrophage activation

Question

Quizplus · Accepted Answer

The first event in defense against bacteria is the activation of macrophages, which are the first line of defense against bacterial invasion. They recognize and engulf bacteria and then release chemical signals that activate the immune system. Antibodies, B cells, T cells, and interferons are all involved in the immune response, but they are activated after the macrophages have begun the defense. Therefore, choice E (macrophage activation) is the best choice.

Which of the Following Is the First Event in Defense