The small capillaries in the lungs are in close contact with the alveoli. A red blood cell takes up oxygen during the 0.5 s that it squeezes through a capillary at the surface of an alveolus. What is the diffusion time for oxygen across the 1-μm -thick membrane separating air from blood? Assume that the diffusion coefficient for oxygen in tissue is 2×10−11m2/s.

4. if a cell is placed inside a solution that has a higher concentration of solute than on the inside of the cell, what can be said about the movement of water? a. water will move out of the cell, causing it to shrivel. b. water will move in and out of the cell at the same rate. c. water will move out of the cell, causing it to swell. d. water will move into the cell, causing it to swell.