蛋白质是20种氨基酸彼此以肽键相连而成的生物高分子。机体生物合成的蛋白质分子中的氨基酸种类和排列顺序,是由信息核糖核酸分子中核苷酸种类和连接顺序来决定的。信息核糖核酸分子中每三个相邻的核苷酸构成一种“密码”,它决定蛋白质多肽链中氨基酸种类,20种氨基酸有它们专一相对 Proteins are biopolymers in which 20 amino acids are linked to each other by peptide bonds. The type and arrangement of amino acids in the body’s biosynthetic protein molecules are determined by the type and sequence of nucleotides in the information ribonucleic acid molecule. Every three adjacent nucleotides in an RNA molecule make up a “password,” which determines the type of amino acids in the polypeptide chain of the protein. The 20 amino acids have their specific relative