- 29.8: Urine Composition and Function
- Urine is a liquid byproduct of the body secreted by the kidneys through a process called urination and excreted through the urethra. The normal chemical composition of urine is mainly water content, but it also includes nitrogenous molecules, such as urea, as well as creatinine and other metabolic waste components. Other substances may be excreted in urine due to injury or infection.
Thumbnail: Capillary blood from a bleeding finger. (CC BY 2.0; Crystal (Crystl) from Bloomington, USA).