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  • General

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  • 卵细胞

    A human egg cell surrounded by sperm cells, illustrating fertilization and reproduction.

     

    What's amazing about these cells?
    ::这些细胞有什么了不起的?

    Many things. A human egg . Just add and you have the necessary ingredients for a new baby. What's amazing about these cells is that they are all produced before the girl is even born. Before the girl is even born, plans for the next generation have begun. And that is the start of an amazing process.
     ::许多东西。 人类卵细胞。 添加一个新婴儿所需的元素。 这些细胞的惊人之处在于它们都是在女孩出生之前产的。 在女孩出生之前, 下一代的计划就已经开始了。 这就是一个惊人过程的开始。

    Egg Production
    ::卵生产

    At birth, a female’s ovaries contain all the eggs she will ever produce. However, the eggs do not start to mature until she enters . After menarche , one egg typically matures each month until a woman reaches middle adulthood .
    ::母卵子在出生时就包含所有她会生产的蛋。 然而,卵子在进入之前不会开始成熟。 在经经期后,每个月都会有一个蛋成熟,直到妇女成年。

    Oogenesis
     ::卵生成

    The process of producing eggs in the ovary is called oogenesis . Eggs, like sperm, are haploid cells, and their production occurs in several steps that involve different types of cells, as shown in Figure . You can follow the process of oogenesis in the figure as you read about it below.
    ::卵巢中产卵的过程被称为卵的产卵过程。卵子和精子一样,是杂交细胞,其产卵过程分为几步,涉及不同种类的细胞,如图所示。您可以在下面读到的图中跟随卵子的产卵过程。

    Flowchart depicting the stages of oogenesis, illustrating egg cell development.

     

    Oogenesis. Oogenesis begins before birth but is not finished until after puberty. A mature egg forms only if a secondary oocyte is fertilized by a sperm.
    ::发源。 产卵始于出生前,但直到青春期后才结束。 只有当子卵子受精时, 才会形成成熟的卵蛋。

    Oogenesis begins long before birth when an oogonium with the diploid number of undergoes . It produces a diploid daughter cell called a primary oocyte . The primary oocyte, in turn, starts to go through the first of (meiosis I). However, it does not complete meiosis until much later. The primary oocyte remains in a resting state, nestled in a tiny, immature follicle until puberty.
    ::出生前很久, 开始于一个具有低湿度的受体数的。 它产生一个叫做初级卵细胞的低湿度女儿细胞。 主要的卵细胞开始经历第一种( 甲状腺病 I ) 。 但是, 它直到很久之后才完全结结结晶。 主要的卵细胞仍然处于休眠状态, 扎在幼小的不成熟的卵巢中直到青春期。

    Maturation of a Follicle
    ::熔冰的成熟期

    Beginning in puberty, each month one of the follicles and its primary oocyte starts to mature (also see Figure ). The primary oocyte resumes meiosis and divides to form a secondary oocyte and a smaller cell, called a polar body . Both the secondary oocyte and polar body are haploid cells. The secondary oocyte has most of the cytoplasm from the original cell and is much larger than the polar body.
    ::从青春期开始,每个月都有一个卵囊及其主要卵细胞开始成熟(见图 ) 。 主要的卵细胞恢复了 meismois, 并分裂成一个二级卵细胞和一个较小的细胞, 叫做极体。 二级卵细胞和极体都是手动细胞。 二级卵细胞和极体大部分是原细胞的细胞, 并且比极体大得多 。

    Stages of follicle maturation and ovulation in egg production.

     

    Maturation of a Follicle and Ovulation. A follicle matures and its primary oocyte (follicle) resumes meiosis to form a secondary oocyte in the secondary follicle. The follicle ruptures and the oocyte leaves the ovary during ovulation. What happens to the ruptured follicle then? (a) primary follicle, (b) secondary follicle, (c) vesicular follicle, (d) ovulation, (e) corpus luteum forms, (f) regression, (g) corpus albicans.
    ::卵蛋和卵巢的成熟。 卵蛋成熟及其主要卵细胞( 卵蛋) 恢复了 meisis 以形成二级卵细胞。 卵蛋破裂和卵细胞在卵巢期间离开卵巢。 那么破裂的卵蛋会怎样呢 ? (a) 原卵囊, (b) 次卵囊, (c) 卵囊, (d) 卵巢, (e) 元素乳液形式, (f) 回归, (g) 子体。

    Ovulation and Fertilization
     ::输卵和受精

    After 12–14 days, when the follicle is mature, it bursts open, releasing the secondary oocyte from the ovary. This event is called ovulation (see Figure ). The follicle, now called a corpus luteum , starts to degenerate, or break down. After the secondary oocyte leaves the ovary, it is swept into the nearby fallopian tube by the waving, fringelike end (see Figure ).
    ::12 - 14天后,当卵蛋成熟后,它爆发,从卵巢中释放第二子卵细胞。 这个事件被称为排卵(见图 ) 。 现在称为的卵蛋开始退化或崩溃。 在二子卵蛋离开卵巢后,它被挥舞的边缘末端冲入附近的输卵管(见图 ) 。

    The ovary, fallopian tube, and processes of ovulation and egg maturation.

     

    Egg Entering Fallopian Tube. After ovulation, the fringelike end of the fallopian tube sweeps the oocyte inside of the tube, where it begins its journey to the uterus.
    ::排卵后,输卵管的边缘端扫透管内的卵细胞,开始到子宫的旅程。

    If the secondary oocyte is fertilized by a sperm as it is passing through the fallopian tube, it completes meiosis and forms a mature egg and another polar body. (The polar bodies break down and disappear.) If the secondary oocyte is not fertilized, it passes into the uterus as an immature egg and soon disintegrates. 
    ::如果次卵细胞在通过输卵管时被精子施肥,它就会完成 meisisis 并形成成熟的蛋和另一个极体。 (极体分解并消失。 )如果次卵细胞没有受精,它就会作为不成熟的蛋传入子宫,很快会分解。

      

     

    Summary
    ::摘要

    • Immature eggs form in the ovaries before birth.
      ::卵卵在出生前在卵巢中形成
    • Each month, starting in puberty, one egg matures and is released from the ovary.
      ::每个月,从青春期开始, 一个蛋成熟 并释放出卵巢。
    • Release of an egg is called ovulation.
      ::卵的释放被称为排卵。

    Review
    ::回顾

    1. When does a female begin to produce her eggs?
      ::雌性何时开始产卵?
    1. What is a polar body?
      ::什么是极体?
    1. Describe ovulation.
      ::描述排卵。
    1. Predict how blockage of both fallopian tubes would affect a woman’s ability to reproduce naturally. Explain your answer.
      ::预测这两根输卵管的阻塞会如何影响女性自然繁殖的能力。 请解释您的回答 。
    1. Create a flow chart showing the steps in which an oogonium develops into a mature egg.
      ::创建流程图, 显示一个发展成成熟蛋的步骤 。