Multiple Choice
In fish, countercurrent exchange involves water flowing over gills and blood flowing through gill capillaries in opposite directions. This increases gas exchange by creating a(n) ____.
A) larger surface area
B) osmotic gradient
C) concentration gradient
D) reservoir for gas
E) source of new hemoglobin
Correct Answer:

Verified
Correct Answer:
Verified
Q18: The first lungs evolved from outpouchings of
Q19: Gases enter and leave a mammal's body
Q20: The group of animals with an efficient
Q21: Match the structure with the correct description.<br>-bronchioles<br>A)the
Q22: Most of the carbon dioxide produced by
Q24: Which enzyme converts free carbon dioxide in
Q25: Match the respiratory disease or disorder with
Q26: In _, air is pushed from the
Q27: Match the type of respiratory system with
Q66: What is the proper sequence in the