Question

lo 2.1. what is the unique shape of red blood cells that allows them to flow smoothly through the blood vessels?

spherical

biconcave

round

cylinder

flat

Explanation:

Red blood cells have a biconcave shape. This shape increases the surface - to - volume ratio, which is beneficial for gas exchange (such as oxygen uptake and carbon dioxide release). Also, the biconcave shape makes the cells more flexible. This flexibility allows them to squeeze through narrow capillaries (the smallest blood vessels) smoothly. Spherical, round, cylinder, and flat shapes do not provide the same level of flexibility and surface - area - to - volume ratio advantages for the function of red blood cells in blood vessels.

Answer:

B. Biconcave