The digestion of proteins from the diet results in excess amino acids, which need to be excreted safely. In the liver these amino acids are deaminated to form ammoniaAmmonia is a gas at room temperature but readily dissolves in water to form an alkaline solution.. Ammonia is toxicPoisonous. and so it is immediately converted to ureaA nitrogenous waste product resulting from the breakdown of proteins. It is excreted in urine. for safe excretion.
Once we have eaten our food, it is then digested by the body. The digestionThe breakdown of large insoluble food molecules to smaller soluble ones. of proteinOrganic compound made up of amino acid molecules. One of the three main food groups, proteins are needed by the body for cell growth and repair. is broken down by proteaseEnzyme that breaks down proteins. enzymes into amino acidThe building blocks that make up a protein molecule. in the stomach and small intestine.
When excessive amounts of protein are eaten, the excess amino acids produced from digesting proteins are transported to the liver from the small intestine. The liver controls the amino acid concentration in the body, as excess amino acids which need to be excretedDischarged as waste safely. The body is unable to store proteins or amino acids.
In the liver ammonia is formed by the deamination of amino acids. It is highly toxic and cannot be allowed to accumulate in the body. Excess ammonia is converted to urea. Urea and water are released from the liver cells in to the bloodstream and transported to the kidneys where the blood is filtered and the urea is passed out of the body in the urine.