For Air-Breathing Animals, There Is Always a _______ Concentration Gradient

question 179

Multiple Choice

For air-breathing animals, there is always a _______ concentration gradient for diffusion of CO₂ from the _______ to the _______.

• A) small; body; environment
• B) large; environment; body
• C) large; body; environment
• D) small; environment; body
• E) changing; body; environment