|the sequence of metabolic reactions leading in vertebrates to the synthesis of urea|
|a screen or mat covered with a dark material for shielding a camera lens from excess light or glare.|
|a stew of meat, vegetables, potatoes, etc.|
urea cycle n.
The sequence of chemical reactions that takes place in the liver and that results in the production of urea. The key reaction is the hydrolysis of arginine by arginase to ornithine and urea. Also called Krebs-Henseleit cycle, Krebs ornithine cycle, Krebs urea cycle.