Urea
Urea is a soluble form of nitrogen waste produced in the liver from ammonia. It is the primary nitrogenous waste product in mammals and most terrestrial animals.
Birds do not urinate like mammals do. They excrete nitrogenous waste in the form of a semisolid waste called uric acid, which is combined with their feces and expelled together. This helps birds conserve water and maintain a lighter body weight for flight.
the breakdown of proteins in the body. Ammonia is the most toxic waste product and is converted to urea in the liver for excretion. Urea is the main nitrogenous waste in mammals, while uric acid is prevalent in birds and reptiles.
The kidneys remove nitrogenous waste from the blood and produce urine to remove the waste.
Urine contains nitrogenous wastes.
Azotemia or uremia means high blood levels of nitrogenous waste.
nitrogenous waste
uric acid
Kidneys excrete nitrogenous waste (urine) and also regulate the water balance in vertebrates. Rat is a vertebrate, too.
Mollusks have a unique way of excreting nitrogenous waste. It is processed in the excretory organ and released into the water.
Grasshoppers eliminate their nitrogenous waste through the malipighian tubules that are on the digestive tract. Earthworms eliminate their nitrogenous waste by the nephridia.
Kidneys filter nitrogenous waste from the blood.