Nature
|October 24, 1985
PubMed
概括

人类的性别染色体 (X和Y) 通过特定区域的同源DNA序列在半变异过程中配对. 这一区域表现出伪自体遗传,表明在雄性半变异过程中进行重组.

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Chromosome Structure02:40

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Telomeres and Telomerase02:41

Telomeres and Telomerase

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X and Y Chromosomes02:32

X and Y Chromosomes

Among mammals, the gender of an organism is determined by the sex chromosomes. Humans have two sex chromosomes, X and Y. Every human diploid cell has 22 pairs of autosomes and one pair of sex chromosomes. A human female has two X chromosomes, while a male has one X chromosome and one Y chromosome.
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The Y Chromosome Determines Maleness02:19

The Y Chromosome Determines Maleness

The Y chromosome is a sex chromosome found in several vertebrates and mammals, including humans. In addition to 22 pairs of autosomes, the human males have one X chromosome and one Y chromosome. In these organisms, the presence or absence of the Y chromosome determines the development of male traits.
Evolution
Around 300 million years ago, the two sex chromosomes diverged from two identical autosomal chromosomes. Over time, the Y chromosome has lost most of its genes, shrinking in size. Today,...
The Ratio of X Chromosome to Autosomes02:45

The Ratio of X Chromosome to Autosomes

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Genetic Material01:20

Genetic Material

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