urea circulation

例句：

1. 1. The urea cycle is a crucial part of the human body's nitrogen metabolism.
   尿素循环是人体氮代谢中至关重要的部分。
2. 2. During the urea cycle, the amino acid glutamine is converted into glutamic acid.
   在尿素循环过程中，氨基酸谷氨酰胺被转化为谷氨酸。
3. 3.A defect in the urea cycle can lead to a condition called urea cycle disorder, which requires specialized treatment.
   尿素循环缺陷可能导致一种称为尿素循环紊乱的疾病，需要特殊的治疗。