That is what a double helix looks like. 这就是二重螺旋线的形状。
Each step of the double helix is a base made up of two kinds of nucleic acid. 每阶二重螺旋线都是一个碱基,由两种核酸组成。
It provided strong evidence of the structure of D-N-A as a double helix. 它为脱氧核糖核酸结构呈双螺旋线提供了有力证据。
Many of the databases along the double helix were shut down, closed, so that you began to function with very little data. 许多数据库是顺着双螺旋线停止运行,关闭,让你们开始运行很少的数据。