The rear engine was considerably longer, and the support struts connecting the cockpit ball to the wings were much thicker than standard.

其后引擎相当长。其连接球型驾驶舱和机翼的支柱比标准支柱粗得多。

youdao

It's the phosphate and the pentose that make up the backbone - that make up the upright struts of the ladder and it's the bases that make up the connecting struts, so the bases are the colors.

磷酸基和戊糖,共同构成了主链,主链又构成了梯子上下的支柱,而碱基,则构成连接支柱的梯阶,碱基是用各种颜色表示的

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