At that time the United States did not stretch all the way across the continent.

VOA: special.2010.01.11

Every cell in your body has exactly the same DNA; that is if I could stretch out all the DNA and look at the base pair sequence, the sequences of bases along all the DNA in your chromosomes, they'd be identical in all the cells.

身体内每一个细胞都有完全相同的DNA,如果我把整条DNA展开,然后检查其碱基对的顺序,你体内每个细胞中染色体上,DNA的碱基对顺序,都是完全相同的

耶鲁公开课 - 生物医学工程探索课程节选