They are trying to find their way through the zona pellucida, the membrane that surrounds and protects the egg. 

它们试图找到通过保护卵细胞的透明带的路。

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So theresearchers needed a method to enhance cracks—similar to the way human graderssqueeze the egg along the crack to see if it opens.

因此，研究人员需要一种增大裂缝特征的方法——就跟分级员沿着裂缝挤压鸡蛋，看它是否裂开的方法相似。

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Egg tarts are just one way that Yum is becoming the Hallmark of the East.

蛋挞仅是百胜餐饮跻身东方市场的一种方式而已。

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So if you think of a shell, you can actually just think of an egg shell, that's probably the easiest way to think of it, where the yolk, if you really maybe make it a lot smaller might be the nucleus.

可以把它想成，个蛋壳，这也许是，最简单的思考办法,蛋黄如果，缩小非常多倍的话,就可以想象成核子。

麻省理工公开课 - 化学原理课程节选

And that certainly wasn't true way back at the start of A, as the fertilized egg first begins to split and multiply, subdivide and make organs.

显然不是在A阶段这么早就开始的，当受精的卵子开始分裂繁殖，继续分裂，形成器官。

耶鲁公开课 - 死亡课程节选

This is the idea that a hen is merely an egg's way of making another egg.

ECONOMIST: Ageing

Listening to the judgment in his shirtsleeves, his suit jacket having been the casualty of a well-aimed egg on his way into court, he showed no signs of regret or even discomfort.

ECONOMIST: Slugging through the mud | The

Salmonella can make its way inside the egg in the reproductive tract of a hen before the shell is formed.

FORBES: To Fridge of Not to Fridge?