Urea

The proteins in our food contain more nitrogen than our bodies need in order to function. Our liver converts this nitrogen surplus into urea, which our kidneys then secrete in urine.

Because urea contains lots of nitrogen, it is a good plant fertilizer. Plants need nitrogen in order to make amino acids – in other words, in order to grow. Urea is also used in ointments and creams.

The synthetic manufacture of urea was an important milestone in chemistry and marked the birth of biochemistry. The synthesis process showed that it was possible to make an organic product in the laboratory, without using biological raw materials. Before then people didn’t believe this was possible.