Question

select all that apply
red blood cells are biconcave in shape. list three advantages that this shape confers upon the rbcs.
there is more surface area for sodium channels that are needed for red blood cell function.
there is an increased surface area for diffusion of gases.
the cell membrane is close to hemoglobin molecules.
the cells can divide rapidly when more rbcs are needed.
the cells can readily squeeze through narrow capillaries.

Explanation:

1. The biconcave shape of RBCs increases surface - area to volume ratio, facilitating gas diffusion. So, "There is an increased surface area for diffusion of gases" is correct.
2. The biconcave shape brings the cell membrane closer to hemoglobin molecules, enhancing oxygen - binding and release. So, "The cell membrane is close to hemoglobin molecules" is correct.
3. The flexible biconcave shape allows RBCs to squeeze through narrow capillaries. So, "The cells can readily squeeze through narrow capillaries" is correct. RBCs are non - nucleated and cannot divide rapidly, and the shape is not mainly related to sodium channels for their function.

Answer:

• There is an increased surface area for diffusion of gases.
• The cell membrane is close to hemoglobin molecules.
• The cells can readily squeeze through narrow capillaries.