Discuss about ammonia

In aquatic animals, such as fish, ammonia is excreted directly into the surrounding water through diffusion across the gills. This method is efficient because water helps dilute ammonia, reducing its toxicity. However, this process requires a large volume of water, making it less suitable for terrestrial organisms.

In contrast, terrestrial animals, including mammals, convert ammonia into less toxic substances like urea or uric acid to conserve water. Urea is formed in the liver through the urea cycle, where ammonia is combined with carbon dioxide. This conversion allows for safer storage and excretion of nitrogenous waste.

Ammonia plays a crucial role in the nitrogen cycle, where it is produced by the decomposition of organic matter and is utilized by plants as a nutrient. However, high concentrations of ammonia in the environment can be harmful, leading to toxicity in aquatic ecosystems.