Which of the following is considered an agranulocyte?

An agranulocyte is a type of white blood cell that does not have visible granules in its cytoplasm when viewed under a microscope. Monocytes fall into this category as they are characterized by their large size and kidney-shaped nuclei, lacking the cytoplasmic granules that are prevalent in granulocytes.

In contrast, neutrophils, eosinophils, and basophils are all classified as granulocytes because they contain distinct granules that can be seen with a standard stain. These granules play significant roles in the immune response, but their presence distinguishes them from agranulocytes like monocytes. Monocytes, once activated and matured, can further differentiate into macrophages and dendritic cells, which are essential for phagocytosis and antigen presentation, respectively. Thus, the classification of monocytes as agranulocytes emphasizes their unique functional characteristics in the immune system.