Along with fat and carbohydrates, protein is considered a "macro-nutrient," which means that the body requires large amounts of it; however, unlike fat and carbohydrates, the body does not store protein, so it needs to be acquired through the diet, according to WebMD.
Protein is an important element of every cell that makes up a body, notes WebMD. The body needs protein to fabricate and fix various tissues. Enzymes, hormones, bones, muscles, cartilage, skin, and blood are also constructed from protient.
Proteins are composed of amino acid monomers linked together by peptide bonds in long polypeptide chains, explains Dr. John W. Kimball. One or more polypeptide chains organized together form a protein. Carbohydrates are polysaccharides composed of monosaccharide sugar subunits. Fats are composed of glycerol and fatty acid subunits.
Proteins are synthesized by a linear assembly process called translation, utilizing 20 different types of amino acid. Kimball explains that a ribosome acts on mRNA, translating a blueprint for the required protein sequence. tRNA transfers the necessary amino acids to the ribosome where it covalently bonded to the next sequential amino acid to form the polypeptide chain. Translation is a unique process that only proteins undergo.