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  • General

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  • 门德尔第一次实验

    What you will learn
    ::你会学到什么

    • Mendel’s first with
      ::门德尔第一位
    • What were the results of F1 and F2 generations
      ::F1和F2世代的结果是什么?
    • Mendel’s first law of inheritance: the law of segregation
      ::门德尔第一部继承法:隔离法

    A close view of green peas, showcasing round and wrinkled shapes.

    Peas. Some round and some wrinkled. Why?
    ::豆子 一些圆的 一些皱纹 为什么?

    That's what asked. He noticed peas were always round or wrinkled, but never anything else. Seed shape was one of the traits Mendel studied in his first set of experiments.
    ::这就是问题所在。他注意到豆子总是圆的或皱纹的, 但从来就没有别的东西。 种子形状是他第一组实验中研究的孟德尔的特质之一。

    Mendel’s First Set of Experiments
    ::门德尔第一组实验

    Mendel first experimented with just one characteristic of a pea plant at a time. He began with flower color. As shown in the  Figure , Mendel cross-pollinated purple- and white-flowered parent plants. The parent plants in the experiments are referred to as the P (for parent) generation . 
    ::门德尔第一次实验时只用一个豆子厂的特征。 他先用花色开始, 如图所示, 门德尔交叉污染的紫花和白花的母植物。 实验中的母植物被称为P( 父母) 一代 。

    Mendel's pea plant experiments: P generation, F1 generation, and F2 generation flower colors.
    This diagram shows Mendel's first experiment with pea plants. The F1 generation results from cross-pollination of two parent (P) plants, and contained all purple flowers. The F2 generation results from self-pollination of F1 plants, and contained 75% purple flowers and 25% white flowers. This type of experiment is known as a monohybrid cross.

    F1 and F2 Generations
    ::F1和F2代

    The offspring of the P generation are called the F1 (for filial, or “offspring”) generation . As you can see from the  Figure , all of the plants in the F1 generation had purple flowers. None of them had white flowers. Mendel wondered what had happened to the white-flower characteristic. He assumed some type of inherited factor produces white flowers and some other inherited factor produces purple flowers. Did the white-flower factor just disappear in the F1 generation? If so, then the offspring of the F1 generation—called the F2 generation —should all have purple flowers like their parents.
    ::P一代的后代被称为F1(为F1,或“牺牲”)一代,从图中可以看出,F1一代的所有植物都有紫花,其中没有一个是白花,门德尔想知道白花特性发生了什么,他假定某种继承因素会产生白花,另一些继承因素产生紫花,白花系数是否在F1一代中消失了?如果是这样,那么F1一代的后代,即所谓的F2一代,应该都有像父母一样的紫花。

    To test this prediction , Mendel allowed the F1 generation plants to self-pollinate . He was surprised by the results. Some of the F2 generation plants had white flowers. He studied hundreds of F2 generation plants, and for every three purple-flowered plants, there was an average of one white-flowered plant.
    ::为了检验这一预测,门德尔允许F1代植物自我污染。他对结果感到惊讶。一些F2代植物有白花。他研究了数百种F2代植物,每三个紫花植物中平均就有一座白花植物。

    Law of Segregation
    ::隔离法

    Mendel did the same experiment for all seven pea . In each case, one value of the characteristic disappeared in the F1 plants and then showed up again in the F2 plants. And in each case, 75 percent of F2 plants had one value of the characteristic and 25 percent had the other value. Based on these observations , Mendel formulated his first law of inheritance. This law is called the law of segregation . It states that there are two factors controlling a given characteristic, one of which dominates the other, and these factors separate and go to different gametes when a parent reproduces.   
    ::Mendel对所有7个豆类做了同样的实验。在每种情况下,一个特性的价值在F1工厂消失,然后在F2工厂再次出现。在每一种情况下,75%的F2工厂有一个特性的价值,25%的F2工厂有另一个价值。根据这些观察,Mendel制定了他的第一个继承法。这部法律被称为隔离法。它指出,有两个因素控制着一个特定特性,其中一个因素主宰着另一个特性,这些因素在父母繁殖时又分开,转到不同的调子。

     

     

     

     

    Summary
    ::摘要

    • Mendel first researched one characteristic at a time. This led to his law of segregation. This law states that each characteristic is controlled by two factors, which separate and go to different gametes when an organism reproduces.
      ::Mendel每次首先研究一个特征,这导致了他的隔离法,该法规定,每种特征都受两个因素控制,在生物体繁殖时,这两个因素将分离到不同的偶数中去。

    Review
    ::回顾

    1. Describe in general terms Mendel’s first set of experiments.
      ::概括地描述Mendel的第一套实验。
    2. State Mendel's first law.
      ::孟德尔州第一部法律
    3. Assume you are investigating the inheritance of stem length in pea plants. You cross-pollinate a short-stemmed plant with a long-stemmed plant. All of the offspring have long stems. Then, you let the offspring self-pollinate. Describe the stem lengths you would expect to find in the second generation of offspring.
      ::假设你正在调查豆子植物干线的继承问题。你将一个长长的植物,划出一个短短的植物。所有的后代都有长长的长的长的长的长的长的长的长的长的长的长的长的长的长的长的,然后你任随后代自圆其说。你描述一下在第二代后代中你会找到的干长的长度。