Explain the urea cycle, Science

Explain the Urea Cycle ?

From our discussion above, it is clear that the amino group of all amino acids is ultimately converted to ammonia (NH3). Ammonia is highly toxic to the nervous system. Hence, it must be removed. How is this done? Basically, ammonia combines with C02 to form urea, which is not toxic to the body. Hence, one of the major end products of protein metabolism is urea.

Urea is the major disposal form of amino groups derived from amino acids and accounts for 90% of the nitrogen containing compounds of urine. One of the nitrogen of the urea molecule is supplied by free NH, and the other one by aspartate. Glutamate is the immediate precursor of both ammonia and aspartate nitrogen. The carbon and oxygen of urea are derived from C02. Urea is produced by the liver and is then transported in the blood to the kidneys for excretion in the urine. The steps involved in converting ammonia to urea include


Most of our nitrogenous waste comes from the breakdown of amino acids. This occurs by deamination. Deamination of amino acids results in the production of ammonia (NH3) as we learnt above. Ammonia is an extremely toxic base and its accumulation in the body would quickly be fatal. However, liver contains a system of carrier molecules and enzymes which quickly converts the ammonia (and carbon dioxide) into urea. This is called the 'urea cycle'. This entire sequence of urea cycle is discussed below, along with the enzymes involved in the synthesis of urea.


Posted Date: 5/20/2013 6:04:18 AM | Location : United States

Related Discussions:- Explain the urea cycle, Assignment Help, Ask Question on Explain the urea cycle, Get Answer, Expert's Help, Explain the urea cycle Discussions

Write discussion on Explain the urea cycle
Your posts are moderated
Related Questions
Explain the Composition of Bile Bile is a complex fluid. It is yellowish green in colour and bitter in taste. It consists of: Water Mineral salts (chloride, potassium

hi can you help me on my science

What does regolith mean? Ans) This refers to a layer of loose surface material covering bedrock.

Pluto: Pluto's  existence was also proposed  to account for deviations in the orbit of Uranus. Even after the influence of Neptune~had  been accounted for, an American astron

Why does marble rarely contain fossils? This is due to of the way that it is formed. When you have a rock that is formed bymetamorphosis then it has been created by heat and pres

how can the theoretical paradigms be used to describe family in Kyrgyzstan?

Explain the process of leaching- Temperature High temperatures hinder the process of leaching and cause an upward movement of soluble salts.  Wherever, moisture conditions are

what is diffusion.

How do minerals become rocks and rocks become soil? Ans) Minerals become rocks by pressure and temperature, often deep inside the earth's core, or easily through pressure for i

Personal sensitivity : There are other dangers from substances which are not so common. e.g. mutagens , but one aspect we have not mentioned involves you. The eyes, lungs and skin