Question

The advantage of RBCs being biconcave is that
A. They increase the surface area.
B. They can be packed up like coins.
C. They can fit into capillaries.
D. None of the above.

Answer 1

Hint: RBC is characterized by the disc-shaped body and concave center. They lack nucleus, nuclear DNA, and most organelles. So, they cannot divide or replicate like other cells of the body. RBCs are transported through the body by blood flow and pressure.

Complete answer:

RBCs are Commonly known as red blood cells, or erythrocytes are the blood cells that are essentially involved in the transportation of oxygen to body tissues from the lungs and carbon dioxide from the body tissues to the lungs to be excreted out from the body.

The biconcave shape of cells is the most important adaptation of the red blood cells. 

In general, erythrocytes are biconcave in shape or they are shaped like a doughnut but without a hole at the centre. This important adaptation ultimately allows the cells to carry oxygen molecules more efficiently and effectively. 

The biconcave shape of RBCs increases the cell’s surface area thereby allowing more haemoglobin to be stored in the cell. So, more amounts of Hb can bind with more oxygen to transport. The larger surface area of RBCs provides more exchange of oxygen and carbon dioxide. 

Due to such a shape, RBC can swell easily and squeeze easily through small capillaries without any rupture or damage. Hence, the advantage of RBCs being biconcave is that it increases the surface area.

Hence, option A is the correct option.

Note: If RBC had a spherical shape naturally, then it would have been subjected to stress and break down easily. Red blood cells are involved in the transportation of oxygen for the process of respiration, but they do not consume any oxygen for themselves. RBCs may undergo deformations after being exposed to external forces. Red blood cells have also been shown to be capable of reverting to biconcave discoid shape even though they undergo deformation.