Question

why is rate of breathing difference between Terrestrial and aquatic animals

Answer 1

Aquatic animals take in the oxygen dissolved in water. The amount of dissolved oxygen in water is fairly low compared to the amount of oxygen in the air. Therefore, rate of breathing in aquatic organisms is much faster than in terrestrial organisms.

Answer 2

in the land the oxygen is dissolved in air whereas in water oxygen is dissolved in less amount so aquatic animals respire faster than terrestrial animals