With a shortage of chromosomes, a developing fetus will likely grow into a child with down syndrome.
如果缺省染色体,一个处于成长阶段的胚胎可能发育成一个具有不良综合症的小孩。
So the number of stars that we know exist is now estimated at about 300 million million million.
因此,我们所知道的现有恒星数目估计约有30亿×1000亿颗。