Urea is an organic chemical made up of nitrogen, carbon and hydrogen that is produced in the body as a by product of extracting energy from proteins. It is filtered by the kidneys and excreted in urine. It forms the majority of the non-water composition of urine and is responsible for the color and smell of urine. The concentration of urea in urine can vary widely and the color and concentration of urine can be a sign of other disorders, such as dehydration or kidney failure.
If urea is not removed from the body, it will eventually poison the body's organs, resulting in death.
Urea was the first organic chemical to be synthesized outside the body. Prior to this, chemists believed that organic molecules could not be synthesized. This discovery paved the way for the synthesis of organic chemistry and inorganic chemistry into the same field of study.