Question

Choose the correct answer from the alternatives given.
In human lungs, gas exchange occurs at the

• A. two bronchi
• B. alveolar sacs
• C. pleural sacs
• D. both (b) and (c)

Answer 1

The correct option is B alveolar sacs

In humans, gas exchange occurs in the lungs between the alveoli and the capillaries located on the walls of the alveoli. The inhaled oxygen moves from the alveoli to the blood in the capillaries, and carbon dioxide moves from the blood in the capillaries to the air in the alveoli. So, the correct option is 'alveolar sacs'.