R.B.C. has shape, a biconcave..WHY?
Red blood cells, or erythrocytes, are biconcave for two reasons.
erythrocytes have no nucleus or internal membranes.
have an unusual cytoskeleton. All cells have a cytoskelet…on, which is made
out of long protein polymers, and gives cells their shape. The erythrocyte
cytoskeleton is a dense fibrous structure lining the whole cell and making
many contact points. The primary component of this lining is spectrin, a
long fibrous protein. The spectrin is attached to the membrane at many
points. Spectrin chains help to pull the red blood cell into its
characteristic shape, and allows them to squeeze through tiny capillaries.
Mice that have mutant spectrin have spherical red blood cells, which
illustrates the importance of spectrin in holding the appropriate shape of
The binconcave shape of a red blood cell increases the cell’s surface area and facilitates diffusion of O2 and CO2 into or out of the cell.
The biconcave shape is caused when flowing through capillaries and narrow slits in the spleen.