Here's why:
* Amino Acids: Proteins are made up of long chains of amino acids.
* Nitrogen in Amino Acids: Each amino acid contains a central carbon atom bonded to an amino group (-NH2). This amino group is the primary source of nitrogen in proteins.
* Abundance of Nitrogen: Nitrogen makes up about 16% of the total mass of a typical protein.
While other molecules like nucleic acids (DNA and RNA) and some lipids also contain nitrogen, the sheer abundance of nitrogen in proteins makes them the clear winner.
