Why Does Countercurrent Exchange Optimize Gas Exchange Across Some Gills

question 46

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, allowing diffusion to occur across the entire respiratory surface.
• D) It optimizes delivery of the respiratory medium to the respiratory surface.
• E) It minimizes the area of diffusion.

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Definitions:

Alkane

A hydrocarbon compound consisting only of carbon and hydrogen atoms arranged in a tree structure with single bonds.

Alkane

Saturated hydrocarbons consisting of carbon and hydrogen atoms connected by single bonds in a tree structure, without any cycles or double bonds.

IUPAC Name

The systematic name of a chemical substance as determined by the rules of the International Union of Pure and Applied Chemistry.

Propylnonane

A hypothetical chemical compound, likely meant to represent a molecule composed of a propyl group attached to a nonane backbone, but does not match standard naming conventions.