Granulocytes vs Agranulocytes
Granulocytes and agranulocytes, both are considered as a two types of white blood cells. This classification is based on the presence or absence of cytoplasmic granules, nuclear shape, and affinity for laboratory stains or dyes. White blood cells or leucocytes are considered as a main cellular component of blood. White blood cells are larger than erythrocytes and are found in less numbers than erythrocytes. Unlike erythrocytes, leucocytes can exit the blood by assuming amoeba-like behavior to wriggle through narrow capillary pores, and do their function in various tissues. The main function of leucocytes is to defend the body against infective pathogens and foreign materials. Leucocytes and their derivatives, along with certain plasma proteins are responsible in making the immune system, in many higher organisms.
Granulocytes can be easily differentiated by the color of their granules when stained with Wright’s stain. The three types of granulocytes are neutrophils, eosinophils, and basophils. They are formed in red bone marrow in vertebrates. Neutrophils are the most numerous white blood cells and contain the nuclei with one to five lobes. The main function of neutrophil is to destroy pathogens by phagocytosis. Eosinophils contain irregular shaped nuclei with two lobes, and course, uniform, round or oval shaped granules in their cytoplasm. Eosinophils increase in great numbers in allergic conditions, and are important to ingest and detoxify foreign proteins. Basophils represent the least numerous white blood cell type and contain centrally located, S-shaped nuclei. Basophils perform phagocytosis, and they release herpin and histamine, and promote the inflammatory responses in organisms.
There are two types of agranulocytes, namely Monocytes and Lymphocytes. These cells do not have granules in their cytoplasm. Monocyte is the largest white blood cell type and contains horse shoe-shaped nucleus. The main function of monocyte is to carry out phagocytosis of cellular debris and foreign particles. Lymphocyte is normally the second numerous white blood cells type and contains one large, spherical nucleus. The two types of lymphocytes are T lymphocytes and B lymphocytes. T lymphocytes directly attack infected cells, and they do not make antibodies. Unlike T lymphocytes, B lymphocytes produce antibodies and release into the blood stream to circulate and attack foreign particles. Monocytes make up 1-7%, while lymphocytes make up 15 to 30% of total white blood cells in an adult human.
What is the difference between Granulocytes and Agranulocytes?
• Granulocytes develop from red bone marrow while agranulocytes develop from lymphoid a myeloid tissue.
• Granulocytes consist of eosinophils, basophils, and neutrophils whereas lymphocytes and monocytes are the two types of agranulocytes.
• Unlike granulocytes, agranulocytes lack cytoplasmic granules.
• Granulocytes contain nuclei with lobes, while granulocytes do not have lobed nuclei.
• Granulocytes make up 60% to 70% of total white blood cell count while agranulocytes make up 20% to 30% of it.