MedCa Phlebotomy Technician Practice Exam

Granulocytes are a type of white blood cell that are distinguished by the presence of granules in their cytoplasm. These granules are actually membrane-bound organelles that contain enzymes and other substances crucial for the immune response. The presence of these granules gives granulocytes their name and allows them to perform various functions, including the phagocytosis of pathogens and the release of inflammatory mediators.

While size, the nucleus-to-cytoplasm ratio, and the ability to produce antibodies are characteristics associated with different types of white blood cells, they do not define granulocytes specifically. For instance, other leukocytes may have different sizes or ratios, and lymphocytes, another type of white blood cell, are primarily responsible for producing antibodies, not granulocytes. Therefore, the defining feature of granulocytes is undoubtedly their granules, which are essential for their role in the immune system.