Which of These Statements Applies to Monocytes

Question

Which of these statements applies to monocytes
A)They are the first phagocytes to exit the blood and arrive at an injured or invaded area.
B)They swell and mature into macrophages after exiting the blood.
C)They act as opsonins.
D)They may differentiate into plasma cells.

Accepted Answer

Monocytes are the largest type of white blood cells and they have a distinct horseshoe-shaped nucleus. They are produced in the bone marrow and circulate in the blood for about a day before exiting into the tissues where they mature into macrophages. Once they mature, they can phagocytize foreign particles and cellular debris, and initiate an immune response by presenting antigens to T cells. Option A is incorrect because neutrophils are the first phagocytes to arrive at an injured or invaded area. Option C is incorrect because opsonization is the process of coating foreign particles with antibodies or complement proteins to increase their phagocytosis by other cells, which is not a function of monocytes. Option D is incorrect because plasma cells are derived from activated B cells, not monocytes.