Question

Why is there a difference in the rate of breathing between aquatic organisms and terrestrial organisms? Explain.

Answer 1

Hint: The availability of oxygen in water and atmosphere is different. Aquatic animals can breathe the oxygen which is dissolved in the water.

Complete Answer:
- Breathing or ventilation is the process of transferring air to and from the lungs to make the exchange of gas with the internal atmosphere easier, particularly through bringing in oxygen and flushing out carbon dioxide.
- All vertebrates breathe with their lungs through a strongly ramified pipe system or airways that lead from their nose to the alveoli, which consist of regular inhalation cycles.
- The respiratory cycles per minute or the rate of breathing is one of the four primary signs of life. The breadth depth and rates in normal conditions are regulated automatically, and unconsciously, by multiple homeostatic mechanisms, which maintain a constant arterial blood partial pressure, carbon dioxide and oxygen.
- Aquatic species such as fish receive oxygen through their gills from water present in a dissolved state. The dissolved oxygen is comparatively low in water as compared to oxygen in the atmosphere.
- The rate of breathing of aquatic animals is higher than that of terrestrial organisms because they have to respire more to achieve more oxygen because the concentration of dissolved oxygen of water is much less than that of oxygen available in air.

Note: All vertebrates are breathed via repeated inhale and exhale cycles through a highly ramified tube or airways leading from nose to alveoli. The sum of breathing or respiratory cycles per minute is one of the four primary signs of life. The depth and breathing rate are automatically regulated, and without consciousness, under normal conditions by several homeostatic mechanisms which constantly maintain the partial carbon dioxide and oxygen pressures in the blood.