How do life processes in aquatic organisms differ from terrestrial ones?

Aquatic organisms primarily differ from terrestrial ones in their methods of respiration, locomotion, and reproduction.

Aquatic organisms have adapted to their environment in unique ways that differ significantly from their terrestrial counterparts. One of the most notable differences is in the process of respiration. While terrestrial organisms typically breathe air directly through lungs, aquatic organisms, such as fish, utilise gills to extract oxygen from water. This is a more complex process as oxygen levels in water are significantly lower than in air, requiring a more efficient extraction method. Some aquatic organisms, like dolphins and whales, have lungs and breathe air, but they have adapted to hold their breath for extended periods while underwater.

Locomotion is another area where aquatic and terrestrial organisms differ. In water, buoyancy reduces the impact of gravity, allowing organisms to move in three dimensions. Aquatic organisms have developed streamlined bodies and specialised appendages like fins and flippers to navigate this environment. Terrestrial organisms, on the other hand, primarily move in two dimensions and have developed legs and wings for locomotion.

Reproduction in aquatic organisms also varies from terrestrial ones. Many aquatic organisms release their eggs and sperm directly into the water, a process known as spawning. This method is less common in terrestrial organisms, which typically have internal fertilisation and often care for their young. However, there are exceptions in both environments, such as seahorses, which have internal fertilisation, and reptiles, which lay eggs.

Lastly, the sensory systems of aquatic organisms have adapted to the different physical properties of water. For instance, sound travels faster and further in water than in air, and many aquatic organisms, such as dolphins, use echolocation, a method of producing sounds and listening for their echoes, to navigate and find food. In contrast, terrestrial organisms rely more on vision and smell, as sound does not travel as efficiently in air.

In conclusion, while all life processes aim to support survival and reproduction, the specific methods and adaptations used by aquatic and terrestrial organisms can vary greatly due to the differences in their environments.