| 1. | In addition to blood formation , vitamin b12 is also involved in the biosynthesis of methyl groups , and thus , has an indirect but strong impact on the synthesis of purine and pyrimidine nucleotides , which are parts of nucleic acids , the building blocks of dna 除了造血所需,维生素b12也叁与甲基的生合成,因此间接也对嘌呤嘧啶等核酸成分的合成有重大影响。 |