Which statement best describes the role of the lung in gas exchange?
It takes in oxygen from the bloodstream.
It produces carbon dioxide as a waste product of cellular respiration.
It extracts oxygen from the atmosphere for use by body cells.
It provides carbon dioxide to the capillaries.

Question

Which statement best describes the role of the lung in gas exchange? 
       It takes in oxygen from the bloodstream.
       It produces carbon dioxide as a waste product of cellular respiration.
       It extracts oxygen from the atmosphere for use by body cells.
       It provides carbon dioxide to the capillaries.

anonymous · Answer

It extracts oxygen from the atmosphere for use by body cells.