ammonia cycle
11urea cycle — a series of metabolic reactions, occurring in the liver, by which ammonia is converted to urea using cyclically regenerated ornithine as a carrier. See illustration. Urea cycle. Diagrammatic representation of reactions by which excess nitrogen in …
12carbamoyl-phosphate synthase (ammonia) — car·bam·o·yl phos·phate syn·thase (am·mo·nia) (kahr bamґo əl fosґfāt sinґthās ə moґne ə) [EC 6.3.4.16] an enzyme of the ligase class that catalyzes the synthesis of carbamoyl phosphate from ammonia and carbon dioxide, the …
13Sulfur-iodine cycle — The sulfur iodine cycle (S I cycle) is a series of thermochemical processes used to produce hydrogen.The S I cycle consists of three chemical reactions whose net reactant is water and whose net products are hydrogen and oxygen. All other… …
14Krebs cycle — krebz n a sequence of reactions in the living organism in which oxidation of acetic acid or acetyl equivalent provides energy for storage in phosphate bonds (as in ATP) called also citric acid cycle, tricarboxylic acid cycle Krebs Sir Hans Adolf… …
15Kalina cycle — The Kalina cycle is a thermodynamic cycle for converting thermal energy to mechanical power, optimized for use with thermal sources which are at a relatively low temperature compared to the heat sink (or ambient) temperature. The cycle uses a… …
16Carnot cycle — Thermodynam. an ideal cycle of reversible engine operations in which a substance at one temperature is compressed adiabatically to a second temperature, expanded isothermally at the second temperature, expanded adiabatically from the second… …
17Phénylalanine ammonia-lyase —   N° EC   EC …
18Human impacts on the nitrogen cycle — Agricultural and industrial nitrogen (N) inputs to the environment currently exceed inputs from natural N fixation (Galloway 2003). As a consequence of anthropogenic inputs, the global nitrogen cycle (Fig. 1) has been significantly altered over… …
19nitrogen cycle — in an aquarium, fish wastes, decaying food and plant material produce ammonia and nitrites which are harmful to the fish. Nitrobacter bacteria convert these wastes into a relatively harmless nitrate in a mature aquarium (see above). The danger to …
20urea cycle — Biochem. a metabolic process by which ammonia derived from amino acids is converted into urea in the liver. Also called Krebs urea cycle. * * * …
