For a gas with low solubility in blood, what primarily determines its rate of transfer into blood?

For a gas with low solubility in blood, what primarily determines its rate of transfer into blood?

• A. Temperature
• B. Alveolar membrane thickness
• C. Gas color
• D. Blood flow

Answer: (D)

When a gas is poorly soluble in blood, the bottleneck for transfer becomes how much blood is flowing through the alveolar capillaries. diffusion into blood is slow because the gas doesn’t dissolve readily, so the amount entering blood during the short capillary passage is limited. If blood flow increases, more gas can be carried away per unit time, raising the overall rate of transfer. Temperature and membrane thickness can influence diffusion, but with low solubility the rate is dominated by perfusion. The gas’s color has no effect on transfer.

When a gas is poorly soluble in blood, the bottleneck for transfer becomes how much blood is flowing through the alveolar capillaries. diffusion into blood is slow because the gas doesn’t dissolve readily, so the amount entering blood during the short capillary passage is limited. If blood flow increases, more gas can be carried away per unit time, raising the overall rate of transfer. Temperature and membrane thickness can influence diffusion, but with low solubility the rate is dominated by perfusion. The gas’s color has no effect on transfer.