Why Does Countercurrent Exchange Optimize Gas Exchange Across Some Gills

question 56

Multiple Choice

Why does countercurrent exchange optimize gas exchange across some gills?

• A) It sustains an optimal thermal environment for gas exchange.
• B) It optimizes perfusion to the respiratory surface.
• C) It sustains an optimal respiratory gas concentration gradient.
• D) It optimizes delivery of the respiratory medium to the respiratory surface.

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