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
Define Ribosomes Ribosomes are small, but complex structures, approximately 20 to 30 nm in diameter, containing two unequally sized subunits, referred to as large and small sub

principle of EDTA..

Chain Reaction: When the atomic nucleus splits, it not only gives off energy, but also throws out two or three more  neutrons.  'These new neutrons can,  in turn,  split two or

A simple equal-arm lever Make a wooden base 15 cm square and 2 cm thick. In the centre of the base fasten one more block of wood 4 cm square and 3 cm thick. Fasten to two sides

Introduction : In any laboratory dealing with biological experiments, hazards can occur mainly due to chemicals and biological materials. In the previous exercise you have done th

Explain Transport - Functions of Plasma Proteins Hormones and several other small molecules travelling in the plasma would themselves get filtered in the renal glomeruli and ge

Explain the Autoregulation function of kidneys The kidneys possess the property of autoregulation. This means that the blood flow in the kidneys remain constant. It is independ