Proteins - Amino acids
Amino acids are biologically important organic compounds containing amine (-NH2) and carboxylic acid (-COOH) functional groups, usually along with a side-chain specific to each amino acid. The key elements of an amino acid are carbon, hydrogen, oxygen, and nitrogen, though other elements are found in the side-chains of certain amino acids. Proteins are large, complex molecules that are critical for the normal functioning of the human body.
They are essential for the structure, function, and regulation of the body’s tissues and organs. Proteins are made up of hundreds of smaller units called amino acids that are attached to one another by peptide bonds, forming a long chain. You can think of a protein as a string of beads where each bead is an amino acid.
The side chains of amino acids give them their different chemical properties and allow proteins to have so many different structures. How many proteins are possible? Protein chains generally vary in size from 100 to 1,000 amino acids in length.