Question

In a healthy human, the most common type of blood cells are
a. Basophils
b. Monocytes
c. Erythrocytes
d. Neutrophils

Answer 1

Hint: In a healthy human, the most common type of blood cells is that cells constitute the largest number of cells in blood and fiction only within the bloodstream. They are non- nucleated and biconcave and also have a life span of one hundred twenty days.

Complete answer:
Blood is a type of specialized connective tissue that is red, vascular, softest, slightly alkaline with a 7.4 pH. It consists of a fluid matrix called plasma and corpuscles.

The corpuscles constitute 45 percent of blood. It includes:
• Red blood cells (RBC) or erythrocytes.
• White blood cells (WBC) or leucocytes.
• Blood platelets.

RBC constitutes the largest number of cells in blood; they function only in the bloodstream. They are non-nucleated and biconcave. This shape of RBC increases the surface area for more Hb binding and gaseous exchange. The spleen is the reservoir for storing RBC and also it is the site of RBC disposal hence called the graveyard of RBCs.

WBC is much larger than RBC but much less in number. It is mainly of two types. Basophils are least in number and function as an anticoagulant. Monocytes are the largest cell of blood and they are actively motile. Neutrophils are abundant and function as phagocytic.
The ratio of WBC and RBC is 1:600.

Hence, the correct answer is option (C).

Note: RBC is specialized for the transportation of oxygen and carbon dioxide as it contains a high amount of haemoglobin and each 100ml blood contains 12-16 gm Hb. WBC are colorless, nucleation, and are the cells of the immune system that are involved in protecting our body against any infection or disease.