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  • 自动somal 托盘 - 高级

    Chromosomes

    How is DNA inherited?
    ::DNA是如何继承的?

    In . The winds up numerous times to form a compact structure. 44 of your 46 chromosomes are autosomes . The other two determine your sex.
    ::你46个染色体中有44个是异体,另外两个决定你的性别。

    Autosomes
    ::自动

    There are 44 autosomes and 2 sex chromosomes in the , for a total of 46 chromosomes (23 pairs). Sex chromosomes specify an organism's genetic sex. Humans can have two different sex chromosomes, one called X and the other Y. Normal females possess two X chromosomes and normal males one X and one Y. An autosome is any chromosome other than a sex chromosome. The figure   shows a representation of the 24 different . The Figure  shows a karyotype of the human genome. A karyotype depicts, usually in a photograph, the chromosomal complement of an individual, including the number of chromosomes and any large chromosomal abnormalities. Karyotypes use chromosomes from the metaphase stage of .
    ::人体可以有两种不同的性别染色体,一种叫X,另一种叫Y。正常女性拥有两个X染色体,而普通男性拥有一个X和Y。一个异体是任何染色体,但性染色体除外。图中显示了24种不同的染色体。图中显示了人类基因组的卡约型。一种卡约型描述,通常是照片中的个人染色体补充,包括染色体的数量和任何大的染色体异常。Karyo型使用来自元相阶段的染色体。

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    The 24 human chromosomes. The autosomes are numbered 1 - 22, based on size, with chromosome 1 being the largest. The X and Y sex chromosomes are shown in the box.
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    A karyotype of the human genome. Is this from a male or female?

    The 22 autosomes are numbered based on size, with the largest chromosome labeled chromosome 1. These 22 chromosomes occur in homologous pairs in a normal diploid , with one of each pair inherited from each parent. The sex of an individual is determined by the sex chromosome within the male gamete . Females are homologous, XX, for the sex chromosomes, whereas males are heterozygous, XY. As all individuals inherit an X chromosome from their mother (females can only produce gametes with an X chromosome), it is the sex chromosome that they inherit from their father that determines their sex.
    ::1. 这22种染色体在正常的染色体中出现,每对一对都从父母中继承。 一个人的性别是由男性染色体中的性别染色体决定的。 女性是同质的,XX,性染色体是同质的,而男性是异性染色体,XY。 由于所有个人都继承母亲的X染色体(女性只能产生带有X染色体的调子),因此他们从父亲那里继承的性染色体决定了他们的性别。

    In terms of genetics , is the location of a gene or trait an important piece of information? Does it make a difference if the gene is located on a sex chromosome or an autosome? It might. Autosomal-linked traits are due to genes on the autosomes; sex-linked traits are due to genes located on the sex chromosomes.
    ::就遗传学而言,基因或特性的位置是否是重要的信息?如果基因位于性染色体或异体上,这有区别吗?它可能。与自动相连接的特性来自异体上的基因;与性别相连接的特性来自性染色体上的基因。

    Simple Dominant Heredity
    ::简单主宰世界

    What is the difference between a trait and a ? Could a disorder be considered a trait? We tend to think of traits as hair color or skin color and disorders as something that is bad for you. But in terms of genetics, a genetic disorder is a trait. Both may be due to your genes. Traits may be inherited in any of a number of ways: autosomal dominant or recessive , , or a more complex pattern of inheritance.
    ::性格和性格有什么区别? 一种病能被视为一种特征吗? 我们倾向于将性格视为发型颜色或皮肤颜色,而疾病则视为对你有害的东西。 但在遗传学方面,遗传病是一种特征。 两者都可能是由于你的基因。 轨迹可能以多种方式继承:自发的支配性或消亡性,或者更复杂的继承模式。

    How are traits due to genes on autosomes inherited? Autosomal traits due to the effects of one gene are usually inherited in a simple Mendelian pattern. That is, they can be either dominant or recessive. In humans, whereas many genetic disorders are inherited in a recessive manner, simple dominant inheritance accounts for many of a person’s physical characteristics, such as chin, earlobe, hairline and thumb shape. For example, having earlobes that are attached to the head is a recessive trait, whereas heterozygous and homozygous dominant individuals have freely hanging earlobes. If you have a cleft chin, a pointed frontal hairline (called a widow’s peak), or a hitchhiker’s thumb, you have inherited the dominant allele for each characteristic from at least one of your parents. Other dominant traits include the presence of hair on the middle section of your fingers, thick lips, and almond-shaped . A widow's peak and hitchhiker’s thumb are displayed in the Figure  , and earlobes are shown in the Figure  .
    ::自然基因的遗传特征如何? 自然基因的遗传特征如何? 自然基因的遗传特征通常以简单的门德利模式传承。 也就是说,它们可以是支配性的,也可以是消逝性的。 在人类中,许多遗传性疾病是以消逝的方式传承的,而简单的主要遗传性遗产则代表一个人的许多身体特征,如下巴、耳垂、发线和拇指形状。例如,将耳垂附在头上是一种消退性特征,而异体和同质动物的主导个体则可以自由地挂起耳垂。如果你有一个左下巴、一个尖尖尖的前额头发(称为遗孀的峰),或者一个搭便车者的拇指,你至少从你的父母之一继承了每种特征的占支配地位。其他主要特征包括手指中间部分的毛发、厚嘴和杏仁形状。图中显示寡妇的峰和搭搭桥人的拇指,图中则显示耳垂。

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    Widow's peak and hitchhiker's thumb are dominant traits controlled by a single autosomal gene.
    Pedigree for earlobe attachment
    Having free-hanging earlobes is an autosomal dominant trait. This figure shows how a family inherited the trait over three generations. Shading indicates people who have the recessive form of the trait. Look at (or feel) your own earlobes. Which form of the trait do you have? Can you tell which genotype you have?

    Summary
    ::摘要

    • There are 44 autosomes and 2 sex chromosomes in the human genome, for a total of 46 chromosomes.
      ::人类基因组中共有44种异体和2种性染色体,共46种染色体。
    • Sex chromosomes specify an organism's genetic sex. Humans have two different sex chromosomes, one called X and the other Y.
      ::人类有两种不同的性染色体,一种叫X,另一种叫Y。

    Review
    ::回顾

    1. What is the difference between an autosome and a sex chromosome?
      ::异体染色体和性染色体有什么区别?
    2. How are autosomal traits usually inherited? Give examples of such traits.
      ::自动细胞特征通常如何继承?请举例说明这些特征。
    3. What is meant by sex-linked?
      ::性关系意味着什么?
    4. A boy is born with an extra finger on one hand. Extra digits are known to be common in members of the father's extended family, but not the mother's. The boy's two sisters have normal fingers. What is the most likely explanation?
      ::男孩出生时双手多指,在父亲的大家庭成员中多指是常见的,但在母亲的大家庭成员中则不常见。男孩的两个姐妹有正常的手指。最可能的解释是什么?