Question

The ratio of RBCs : WBCs in blood is

• A. $30:1$
• B. $600:1$
• C. $1:600$
• D. $50:1$

Answer 1

Answer: (B)

Erythrocytes (Red blood corpuscles or RBCs): Erythrocytes are the most abundant of all cells in the blood. A healthy adult man on an average has 5 millions RBCs mm^-3 of blood. The formation of RBCs is from haematopoietic stem cells and is known as erythropoiesis. It occurs in the red bone marrow in adults.
Leucocytes (White blood corpuscles or WBCs): Leucocytes or white blood corpuscles are colourless due to the lack of haemoglobin. Leucocytes are much lesser as compared to erythrocytes which average about 8000 mm^-3 of blood. Formation of leucocytes is called leucopoiesis.
Thus, the $\frac{R B C}{W B C}=\frac{5000000}{8000}=625:1$