Which of the Following Statements is True

Question

Which of the following statements is true?
A)Oxygen moves into cells by diffusion, but carbon dioxide is moved by active transport.
B)Oxygen and carbon dioxide move into and out of cells and alveoli passively by diffusion.
C)Carbon dioxide and oxygen are actively transported into and out of blood by diffusion.
D)Oxygen moves into cells by diffusion, but in the alveoli it is actively transported.

Accepted Answer

Oxygen and carbon dioxide move into and out of cells and alveoli passively by diffusion. This means that they move from areas of higher concentration to areas of lower concentration without the need for any energy input. Active transport, on the other hand, requires energy input to move substances against their concentration gradient. Therefore, option A and C are incorrect. Option D is also incorrect because oxygen moves into cells by diffusion, not active transport.