What Happens During Countercurrent Exchange in Fishes

question 14

Multiple Choice

What happens during countercurrent exchange in fishes?

• A) Oxygen enters the blood by active transport, and carbon dioxide exits the blood by diffusion.
• B) Gas exchange occurs as blood and water move in the same direction across a respiratory surface.
• C) Oxygen and carbon dioxide move in opposite directions across the respiratory surface by facilitated diffusion.
• D) Oxygen enters the blood by diffusion, and carbon dioxide exits the blood by active transport.
• E) Gas exchange occurs as blood and water move in opposite directions across a respiratory surface.

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Definitions:

Metabolic Acidosis

A condition where there is too much acid in the body fluids, often caused by kidney disease, diabetes, or excessive alcohol intake.

Arterial Blood Gas

A test that measures the levels of oxygen and carbon dioxide in the blood from an artery, used to assess lung function and how well oxygen is being circulated.

Electrolyte

Minerals in the body fluids that carry an electric charge and are essential for muscle function, hydration, and blood pH balance.

Fluid Volume

The amount of body fluids, including blood and lymph, critical for maintaining physiological balance and health.