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

1894_ammonia.png

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
Determine how nitrogen is useful in plant nutrients The supply of nitrogen is related to carbohydrate utilisation. If nitrogen supply is insufficient, carbohydrates will be dep

Method of science: We have seen above that science is an enaeavour  to understand nature and to mould it to satisfy human needs. In earlier units we have seen that, in  this pr

What protist changes shape constantly and flows around it''s food to engulf it

Vitamins: You are, probably, familiar with the names of some of the vitamins. They can be obtained from plant and animal foods. Vitamins are required in small amounts and their

Life in Atmosphere: Just like the earth, the atmosphere also sustains  life. Various types of  insects and mites, birds, bats and other organisms are  some of  the forms tha

What is the earths core made of? Ans) The outer earth core is liquid and the inner is solid. Both parts are of alloy of two metals - iron and nickel, permitting the rise of the

Explain the Sensory Decussation - Feature of Medulla Some of the sensory nerves ascending to the cerebrum from spinal cord cross from one side to the other in the medulla. Card

Explain the Common Tests during Pregnancy Pregnancy, as you may have realized, is a period of physiological stress. To ensure a successful pregnancy, few common tests are recom

Which are clouds formed at the highest altitude: cirrocumulus

Cholagouge action and Absorptive function of bile Cholagouge action: Bile acts as its own stimulus. Bile salts are absorbed from the intestine, carried to the liver and stimula