Does a crocodile get oxygen from water or air?
the respiratory medium of aquatic and terrestrial organisms are water and air respectively.Aquatic animals get oxygen dissolved in water while terrestrial animals get oxygen from atmospheric air.The oxygen content of air is much higher then the oxygen content of water.The ventilation in water is far more difficult than the ventilation in air because water is denser then air. Thus air is the better respiratory medium then water.
The air and oceanic plants. The air above the water is one source. Oxygen from the air simply mixes with the water and dissolves in the ocean. Another source of oxygen is that given off by plants living in the water. Plants use carbon dioxide in the water for photosynthesis. As a result of photosynthesis, oxygen is released.