Therefore, in the liver occur a process called deamination, where an excess of amino acids are broken down. During deamination the amino group is removed to form ammonia. Then the ammonia is modified to the less toxic urea. The urea is removed from the liver via the hepatic vein where in the blood is transported to the heart. From the heart to the kidney, urea is moving via following blood vessels, the aorta to the renal artery.
[online] Available at: http://www.elmhurst.edu/~chm/vchembook/633ureacycle.html [Accessed: 14 Mar 2014]. Cornell University. n.d. AMMONIA & UREA METABOLISM. [online] Available at: https://ahdc.vet.cornell.edu/sects/ClinPath/modules/chem/AMMONIA.HTM [Accessed: 14 Mar 2014]. Biology Mad.
[online] Available at: http://kidshealth.org/teen/your_body/body_basics/endocrine.html [Accessed 10 Nov. 2014]. LiveScience.com, (2014). Endocrine System: Facts, Functions and Diseases. [online] Available at: http://www.livescience.com/26496-endocrine-system.html [Accessed 10 Nov. 2014]. Mayoclinic.org, (2014).
Cells can break down hydrogen peroxide because hydrogen peroxide is poisonous and is a product when the liver breaks down waste therefore enzymes (catalase) must be made in order to deal with it. When the enzyme catalase is added to hydrogen peroxide, oxygen gas is
One of the steps in the cycle the breakdown of arginine into ornithine and urea, a reaction catalysed by the enzyme arginase. (See below) (Fig 1.0) Arginine Orthinine Urea Urease is the enzyme which catalyses the hydrolysis of urea according to the following equation: (NH2)2CO(aq) + 3H2O(l)  CO2(g) + 2NH3(g) The acidic ammonium carbonate is formed because the carbon dioxide dissolves in water to produce carbonic acid (H2CO3), which immediately reacts with ammonia to form the ammonium carbonate. This is shown by the following equation: 2NH3(g) + H2CO3(aq)  (NH4+)2CO3(aq) The resulting solution can then be titrated against hydrochloric acid with methyl orange as the indicator in order to determine how much urea was present initially. The point of neutralisation using a methyl orange indicator is determined using the following colour changes.  Acid  Red.
Ammonia presents as a buffer that neutralizes stomach acid, helping H. pylori to thrive2. As well, catalase enhances its ability to overcome the white blood cells that tries to kill the bacteria1. H. pylori produces two more enzymes right after it colonizes the stomach. Protease and phospholipase are enzymes that act on gastric epithelium to destroy the mucus layer of the stomach1. Surrounding H. pylori, there is a structure called adhesins that enable it to bind to the host cell.
Nitrogen fixation is the conversion of gaseous nitrogen to ammonia. This process is carried out my nitrogen-fixing bacteria in soil and aquatic environments. These bacteria find an enzyme called nitrogenase to break up molecular nitrogen and combine it with hydrogen. Nitrogen fixing bacteria must consume the energy in 12 grams of sugar in order to fix a single gram of nitrogen biologically. The second step, nitrification is the conversion of ammonia to nitrate.