Question

Which one of the following is the smallest?
A. Eosinophil
B. Basophil
C. Neutrophil
D. Monocyte

Answer 1

Hint: They are the white blood cells that play an important role in the inflammatory and immediate allergic response.

Complete answer:
Basophils are the smallest White blood cells and granulocyte. Basophils are slightly smaller than neutrophils and eosinophils. The average diameter of these cells is 8 - 10 µm. They have granules on their surface that are filled with enzymes called heparin and histamine. These enzymes help in allergic reactions and inflammation. It accounts for only 0.5-1% of the overall white blood cells.

Additional Information: -White blood cells are of five main types.
-Cells that have visual granules are named granulocytes whereas those cells that do not have visible granules are called agranulocytes.
-Neutrophils, eosinophils, and basophils are granulocytes whereas Monocytes and lymphocytes are agranulocytes.
-Neutrophils - They are the most abundant white blood cells and are commonly present in the stages of inflammation.
-Eosinophils - The size of the Eosinophil cell is around 12 - 17 µm, it is around 12 - 14 µm in the Neutrophil cell, while the Monocyte cell is around 20 µm.
-Basophils are mostly present in the skin and mucosa tissues which are lining tissues of the opening in the body. The nucleus of the basophils is usually bilobed. Basophils were discovered by German Physician Paul Ehrlich in 1879. The name of basophils comes from the fact that they are susceptible to staining by basic dyes.
-Monocytes - They are the largest WBC’s and help in fighting against infections and also remove the damaged tissues or cells.
-Lymphocytes - They produce antibodies to kill microorganisms and are of two types; T cells and B cells.
-All the white blood cells are derived and produced from multipotent cells called hematopoietic stem cells which are present in the bone marrow.
-All types of WBCs contain a nucleus in their structure that makes it distinguishable from other blood cells.
So, the correct answer is ‘Basophils’.

Note: Basophils contain vasodilator histamine that promotes the blood flow in tissues. Heparin is used as an anticoagulant that prevents blood clotting. CD-200 is a homolog that is produced by herpesvirus-6, herpesvirus-7, and herpesvirus-8 which inhibits the basophil function.