Question

Which one is agranulocyte?
A. Basophil
B. Eosinophil
C. Lymphocyte
D. Neutrophil

Answer 1

Hint: White Blood Cells or WBC(s) are a type of blood corpuscle. They are present in blood and help in formation of the cells of the immune system. Depending on the presence of granules in cytoplasm, WBC(s) can be granulocytes or agranulocytes. Agranulocyte cells can be phagocytic and are responsible for the production of antibodies.

Complete answer:
Option (A) is incorrect. Basophils are granulocyte cells and their cytoplasm contains the characteristic granules. Basophils are the largest granulocytes present and mediate inflammatory immune responses. The Basophils can be stained with basic dyes, hence the name. basophils are known to form in the bone marrow. Their secretions include histamines, and heparins.
Option (B) is incorrect. Eosinophils are granulocytes. They are formed in the bone marrow, but after their transport to the bloodstream, eosinophils do not multiply further. Along with Basophils, these cells mediate inflammatory response and help the body to control allergic reactions. Eosinophils are stained by eosin, an acidic dye which gives them their name.
Option (C) is correct. Lymphocytes are agranulocytes, that is their cytoplasm is devoid of the granules present in granulocytes of WBC(s). Lymphocytes are commonly present in the lymphatic system. Lymphocytes are of three types – B-cells, T-cells and Natural Killer cells. They are known for their ‘memory’ – a property by which they tend to remember the pathogens with which they interact once. This property helps the lymphocyte in faster reaction and elimination in case of a second infection by the same pathogen. In addition, this specific function, lymphocytes help to kill pathogens and protect the body.
Option (D) is incorrect. Neutrophils are granulocyte cells that are formed in the bone marrow. These cells have a highly lobed nucleus. Neutrophils are found in blood and are phagocytic in nature. they migrate to the site of inflammation and internalize pathogens in order to kill them. Neutrophils form an integral part of the innate immunity system.

So, the correct option is C.

Note: Agranulocytes are a part of the immune system of our body that help to eradicate or destroy pathogens. There are two types of agranulocytes – lymphocytes and monocytes. Their major function is to secrete antibodies, perform phagocytosis and kill the invading pathogens. A unique feature of the agranulocytes is their memory by virtue of which they remember pathogens they once encounter. This leads to rapid response and eradication of the same pathogen in case of repeated infections.