Ureotelismi

Ureotelismi is a biological process where animals excrete nitrogenous waste primarily in the form of urea. This is a common strategy among many terrestrial vertebrates, including mammals, adult amphibians, and cartilaginous fishes. Urea is a relatively non-toxic compound that is soluble in water, allowing it to be excreted efficiently in urine. The production of urea occurs in the liver through the urea cycle, a metabolic pathway that converts ammonia, a highly toxic byproduct of protein breakdown, into urea. This conversion is crucial for preventing ammonia poisoning. Animals that are ureotelic typically have kidneys capable of concentrating urine, which helps conserve water while eliminating urea. The evolution of ureotelismi is thought to be an adaptation to life on land, where water conservation is vital. Compared to ammonotelic animals that excrete ammonia directly, ureotelic animals require less water for waste elimination. However, the synthesis of urea is metabolically more costly than ammonia excretion.