S: (n) protein (any of a large group of nitrogenous organic compounds that are essential constituents of living cells; consist of polymers of amino acids; essential in the diet of animals for growth and for repair of tissues; can be obtained from meat and eggs and milk and legumes) "a diet high in protein"
S: (n) carbohydrate, saccharide, sugar (an essential structural component of living cells and source of energy for animals; includes simple sugars with small molecules as well as macromolecular substances; are classified according to the number of monosaccharide groups they contain)
S: (n) lipid, lipide, lipoid (an oily organic compound insoluble in water but soluble in organic solvents; essential structural component of living cells (along with proteins and carbohydrates))
S: (n) nucleic acid ((biochemistry) any of various macromolecules composed of nucleotide chains that are vital constituents of all living cells)