我们吃的很多鸡蛋大部分并不含有胚胎，即使自由圈养的鸡蛋也有可能并没有发展到我们称之为吃小鸡的地步。


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Don Hirose
oviduct

选材／校对／翻译：hqj5715
Don Hirose and a friend had an friendly argument. Don's friend was sure that when you eat an egg you're eating a baby chick, but Don didn’t think so. They made a bet and came to A Moment of Science to have it settled. Before we tell you who has to pay up, let's examine the two situations we’re dealing with. The first, and less common scenario, is eggs that are bought from small farmers–the ones called free-range eggs. These often are fertilized eggs, and can develop into baby chicks. But usually the development process is halted before this happens. When the egg first forms it's only one cell, and is fertilized as it moves down the oviduct to be laid. During the first 24 hours after fertilization the single egg cell divides a few times, forming a little mass of cells. At this point it's technically an embryo (though it doesn't look like a baby chick), but the cells still have not separated into the ones that make eyes, feet, feathers and so forth.
Don Hirose和一个朋友有一个友善的争论。他的朋友非常肯定的说当你吃下一个鸡蛋的时候你吃下的其实是一个小鸡，但是Don却并不这样认为。 他们打了赌并来到科学时刻来一决胜负。在我们告诉你谁需要付赌款之前，让我们分析下我们处理这种事情的两种情况。 第一种且并不是很常见的情况就是鸡蛋买自一些小的农夫--这些鸡蛋被称为“来自自由圈养的蛋。” 这些蛋多数为受精蛋，能够变成小鸡。但是这一发展过程在鸡蛋变成小鸡之前经常会终止。鸡蛋刚刚形成的时候仅仅是一个细胞，在沿着输卵管排出的过程中完成受精。 在受精后的第一个24小时内这一单一细胞进行多次的分裂，形成一个小的细胞团。这时的细胞团技术上可称为一个胚胎（虽然它看上去并不像一个小鸡），但是这些细胞仍没有分开以形成眼睛、脚、羽毛等组织。