So what's going to form the backbone is this continual link, phosphate to sugar, phosphate to sugar, phosphate to sugar, all linked together to form one long, long molecule.

主链是由这样重复的连接构成的,从磷酸到戊糖,周而复始,所有这些连接起来构成一个长链分子

耶鲁公开课 - 生物医学工程探索课程节选

This is - what this diagram shows you is-- the forces that hold these individual strands of DNA into a double stranded form.

你们可以看看这个图表,演示了连接两条DNA长链为双螺旋,结构的化学力

耶鲁公开课 - 生物医学工程探索课程节选