Question

Oxygen in the air diffuses across as it follows its partial pressure gradient into the human body

• A. pleural sacs
• B. a moist respiratory surface
• C. alveolar sacs
• D. both (b) and (c)

Answer 1

The correct option is D both (b) and (c)

The respiratory surface is covered with thin, moist epithelial cells that allow oxygen & carbon dioxide to exchange, these gases can only cross membranes when they are dissolved in water or an aqueous solution.

So, the correct option is 'both (b) and (c)'.