Question

Rate of breathing in aquatic organisms is much greater than that in terrestrial ones. Why?

• A. Aquatic organisms have a greater surface area than terrestrial ones
• B. Aquatic organisms have a greater oxygen intake requirement than terrestrial ones
• C. Amount of dissolved oxygen in water is fairly low compared to that in air
• D. None of the above

Answer 1

The correct option is C

Amount of dissolved oxygen in water is fairly low compared to that in air

Terrestrial animals can breathe the oxygen in the atmosphere, but animals that live in water need to use the oxygen dissolved in water. Since the amount of dissolved oxygen is fairly low compared to the amount of oxygen in the air, the rate of breathing in aquatic organisms is much faster than that seen in terrestrial organisms.