How do granulocytes differ from agranulocytes?

Granulocytes are characterized by the presence of specific granules in their cytoplasm, which can be observed under a microscope. These granules contain enzymes and chemical mediators that are important for the immune response. Granulocytes include neutrophils, eosinophils, and basophils, each with distinct functions in fighting infections and mediating allergic responses. The specific granules in granulocytes are critical for their role in the innate immune response, allowing them to degranulate and release their contents when activated.

In contrast, agranulocytes—such as lymphocytes and monocytes—lack these visible granules in their cytoplasm. While they also play crucial roles in the immune system, their mechanisms of action differ from those of granulocytes and rely more on other features such as receptors on their surface and the ability to produce antibodies or differentiate into macrophages.

Thus, the differentiation between these two types of leukocytes fundamentally lies in the presence of granules in granulocytes, making option A the accurate statement regarding their differences.