In Order to Maximize Diffusion Across the Surfaces of a Gill,oxygen-Rich

Multiple Choice

In order to maximize diffusion across the surfaces of a gill,oxygen-rich water flows in the opposite direction of oxygen-poor blood.This concept is called

A) reverse expiration.
B) pneumonectomy.
C) countercurrent flow.
D) partial pressure saturation.
E) hemoglobin saturation shift.