The fourteen meter-long skeletal remains of a sperm whale hang directly above it.
VOA: special.2011.06.29
This one cell, this one fertilized cell which is unique because it's the - its chromosome contains the combination of the sperm and the egg, develops into an embryo and then on birth develops into a human.
这个受精卵,是独一无二的,因为它的染色体,包含了精子和卵子的组合,并由此发育成为一个胚胎,之后形成一个人类个体
The sperm - say this is the one sperm cell that's able to inject its DNA into the egg, well then this cell has a polarity.
假设某个精子细胞,成功向卵子注入了自己的DNA,那这个细胞就有了极性
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