The tiny oocyte moves along the fallopian tube.

微小的卵母细沿输卵管运动。

The primary oocyte has 46 chromosomes, but eventually it has to turn into a gamete with only 23 chromosomes.

初级卵母细有46条染色体，但是最终会变成只有23条染色体的配子。

But right around birth, the oocytes stop developing — they get stuck in the first stage of meiosis.

但是在的时候，卵母细停止发育——它们卡在减数分裂的第一阶段。

So, during ovulation, the follicle ruptures and releases the egg, which inadvertently leads to epithelial cell damage.

在排卵过程中，卵泡破裂，卵母细，也无意中导致了皮细的损伤。

The truth is, most sperm never reach an oocyte.

事实是，大多数精子永远无法到达卵母细。

And, each follicle is made up of a germ cell, also known as an oocyte, which is the immature egg.

每一个卵泡都由一个殖细组成，也就是卵母细，就是未成熟的卵子。

Those enzymes are the key to getting through the oocyte's protective outer layers.

这些酶是穿过卵母细保护外层的关键。

To do this, the primary oocytes have to complete meiosis 1, and in a person's lifetime only about 400 successfully do that.

要变成配子就必须要经历第一次减数分裂，而一个人的一中大概只有400个初级卵母细可以做到。

If fertilization doesn't happen, then the corpus luteum stops making hormones after around 10 days, becomes fibrotic, and is called the corpus albicans.

如果次级卵母细没有受精，大概10天之后，黄体就会停止放激素而纤维化，形成白体。

After ovulation, the secondary oocyte makes a very quick journey through the peritoneal space and lands in the fallopian tube.

排卵之后，次级卵母细会快速地通过腹膜，最后落入输卵管。

Meanwhile, the primordial follicle turns into a primary follicle, meaning that the follicular cells that surrounding the primary oocyte develop into granulosa cells.

与此同时，包围初级卵母细的滤泡细分化为颗粒细，使始基卵泡变为初级卵泡。

This inner machinery includes two ovaries stocked with thousands of tiny sacks called follicles that each contain one oocyte, an unfertilized egg cell.

这套内部机制包含两个卵巢，卵巢内存有成千万的微小袋子，叫做卵泡，每个卵泡内都含有一个卵母细，即未受精卵细。

Each primordial follicle has a single immature sex cell called the primary oocyte at the core, and a layer of follicular cells surrounds this.

每一个始基卵泡中心都有一个未成熟的殖细，叫做初级卵母细，被卵泡细包裹。

This tells the secondary oocyte to get ready to complete its second meiotic division.

这告诉次级卵母细准备完成第二次减数分裂。

In fact, sometimes only a dozen or so of the original millions make it through all those trials to actually reach an oocyte.

事实，有时候几百万个卵母细中只有一打左右通过了所有这些试验最终得到了卵母细。

The first stage lasts from infancy to puberty, and during this stage the primary oocyte remains stuck in the prophase step of meiosis 1.

第一阶段从婴儿期到青春期，初级卵母细还停留在第一次减数分裂的前期。

You'll remember that during ovulation, about once a month, an ovary releases a secondary oocyte that heads down the fallopian tube and toward the uterus.

你会记得在排卵期，大约一个月一次，卵巢放一个次级卵母细，该卵母细沿着输卵管流向子宫。

Once it's past that, it runs into the zona pellucida, a layer of glycoprotein that covers the oocyte's plasma membrane.

一旦过了这个阶段，它就进入透明带，覆盖卵母细质膜的一层糖蛋白。

These two phases are separated by ovulation, which is when the follicle ruptures and releases an oocyte that is ready to be fertilized.

这两个阶段被排卵分开，排卵即：卵母细被卵泡排，准备好受精。

This triggers the primary oocyte within the dominant follicle to finally complete meiosis 1, and turn into a secondary oocyte, which has 23 chromosomes.

这使得优势卵泡里的初级卵母细最终完成第一次减数分裂，变成了有23条染色体的次级卵母细。