减数分裂(下)
日期:2022-02-23 10:00

(单词翻译:单击)

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Synchronous Process

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同步过程

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During these stages, two centrosomes, containing a pair of centrioles in animal cells, migrate to the two poles of the cell.

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在这些阶段,动物细胞中含有一对中心粒的两个中心体迁移到细胞的两极F)Vzu^XI=R

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The microtubules invade the nuclear region after the nuclear envelope disintegrates, attaching to the chromosomes at the kinetochore.

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核膜解体后,微管侵入核区,附着在着丝粒的染色体上V71A_wR9I4F

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The kinetochore functions as a motor, pulling the chromosome along the attached microtubule.

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动粒起着马达的作用,沿着附着的微管拉着染色体Z82kByNI+Ckt*

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Microtubules that attach to the kinetochores are known as kinetochore microtubules.

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附着在动粒上的微管称为动粒微管7w2YIX^JdX

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Other microtubules will interact with microtubules from the opposite centrosome.

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其他微管将与对面中心体的微管相互作用^&E(r*Oz()[mCyf=SJ@Y

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These are called nonkinetochore microtubules or polar microtubules.

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这些被称为非动粒微管或极性微管f~uYDfnR+jC~Xr8K

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Metaphase 1

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中期1

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Homologous pairs move together along the metaphase plate: the paired homologous chromosomes align along an equatorial plane that bisects the spindle.

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同源染色体对沿着中期板一起移动:成对的同源染色体沿着将纺锤体一分为二的赤道平面排列Gy%xVm^]iEA2j7g.A-CP

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Anaphase 1

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后期1

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Kinetochore microtubules shorten, pulling homologous chromosomes, which consist of a pair of sister chromatids, to opposite poles.

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动粒微管变短,将由一对姐妹染色单体组成的同源染色体拉向相反的两极aJAMpe+xY(-d

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Non kinetochore microtubules lengthen, pushing the centrosomes farther apart.

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非动粒微管变长,将中心体推向更远的距离r(=cZdRff[lv[Wqtr

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The cell elongates in preparation for division down the center.

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细胞向中心伸长,为向下分裂做准备D],7gd.N](H5H)_

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Telophase 1

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末期1

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The first meiotic division effectively ends when the chromosomes arrive at the poles.

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当染色体到达两极时,第一次减数分裂有效地结束3SQT*&K0hA^I%d7

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Each daughter cell now has half the number of chromosomes but each chromosome consists of a pair of chromatids.

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现在每个子细胞都有一半的染色体,但每个染色体都由一对染色单体组成55ulit(0hweYm

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The microtubules that make up the spindle network disappear, and a new nuclear membrane surrounds each haploid set.

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组成纺锤体网络的微管消失,每组单倍体周围都有一层新的核膜hoZ(;MUIW_

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The chromosomes uncoil back into chromatin.

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染色体解卷回染色质HA#VG8ZLB1#^)+3m8!Ie

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Cytokinesis, the pinching of the cell membrane in animal cells or the formation of the cell wall in plant cells, occurs, completing the creation of two daughter cells.

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细胞质分裂,即动物细胞中细胞膜的挤压或植物细胞的细胞壁形成,完成了两个子细胞的产生*+*%GItiBs~]bByjh1Vi

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Sister chromatids remain attached during telophase 1.

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姐妹染色单体在末期1保持附着状态G9WJu%q+,p~]dLyW-Q

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Cells may enter a period of rest known as interkinesis or interphase 2.

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细胞可能会进入一个称为运动间期或间期2nx6z)ES7Eto

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No DNA replication occurs during this stage.

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在此阶段不会发生DNA复制[w1z!%ZV@6CUj

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Meiosis 2

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减数分裂2

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Meiosis 2 is the second meiotic division and usually involves equational segregation, or separation of sister chromatids.

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减数分裂2是减数分裂的第二次分裂,通常涉及相等的分离,或姐妹染色单体的分离9=,Z0mceV3

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Mechanically, the process is similar to mitosis, though its genetic results are fundamentally different.

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从机制上讲,这个过程与有丝分裂相似,尽管它的遗传结果是根本不同的t9dXxBO%B4Mm#n6(Z

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The end result of meiosis 2 is production of four haploid cells, n chromosomes; (23 in humans).

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减数分裂2的最终结果是产生4个单倍体细胞,n条染色体;(人类为23条)8#(4@Oc5!rZ#10_d*p

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The four main steps of meiosis 2 are: prophase 2, metaphase 2, anaphase 2, and telophase 2.

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减数分裂2的四个主要步骤是:前期2、中期2、后期2和末期2C07FWso.ydZelJ3o

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In prophase 2, we see the disappearance of the nucleoli and the nuclear envelope again as well as the shortening and thickening of the chromatids.

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在前期2,我们看到核膜消失,染色单体变短变厚RBwy@ch#m0|az

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Centrosomes move to the polar regions and arrange spindle fibers for the second meiotic division.

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中心体向两极移动,组装纺锤体MJS8l1wkyK1N&JQb

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In metaphase 2, the centromeres contain two kinetochores that attach to spindle fibers from the centrosomes at opposite poles.

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中期2,着丝粒与纺锤丝连结nMoVvA+fX4b*DXz3vHn

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This is followed by anaphase 2, in which the remaining centromeric cohesion is cleaved, allowing the sister chromatids to segregate.

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紧随其后的是后期2,在这一阶段,着丝粒纵裂,姐妹染色单体分离-I^FJyr05C1r6p

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The sister chromatids by convention are now called sister chromosomes as they move toward opposing poles.

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按照惯例,姐妹染色单体现在被称为姐妹染色体,因为它们朝向相反的两极移动A~;PD1!qEF

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The process ends with telophase 2, which is similar to telophase 1, and is marked by the disassembly of the spindle and decondensation and lengthening of the chromosomes.

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这个过程以末期2结束,它与末期1相似,以纺锤体消失和染色体的解聚和加长为标志G]o%njt0Y_H62MH3+N

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Nuclear envelopes reform and cleavage or cell plate formation eventually produces a total of four daughter cells, each with a haploid set of chromosomes.

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核膜的改造和分裂或细胞板的形成最终产生四个子细胞,每个子细胞都有一组单倍体染色体;48-TK=B]z|S|

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Meiosis is now complete and ends up with four new daughter cells.

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减数分裂现在已经完成,最终形成了四个新的子细胞;~bgak-3!.4uH6oaxle

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