-Kumudinee, Subject Matter Expert at Edumarz.
Solution: Aquatic organisms take oxygen dissolved in water unlike the terrestrial organisms who breathe by using atmospheric oxygen. Terrestrial animals are over aquatic organisms as they get free oxygen from the atmosphere as well as air containing more oxygen concentration than water.
The body of aquatic organisms are evolved in the way that they can survive the condition. Hence they use a different approach for extracting the dissolved oxygen in the water.
Organs like gills are specially developed for aquatic respiration.
Terrestrial animals are more comfortable and they can get oxygen directly from air by inhaling the air using lungs.
Respiration in terrestrial and aquatic animals
Terrestrial animals respire through lungs or trachea while aquatic animals respire through gills and skin to get dissolved oxygen.
These adaptations help respective organisms to survive in their habitat.