Meiosis is characterized by the pairing of homologous chromosomes during prophase I. In many species, an elaborate structure called the synaptonemal complex forms between homologues. During this pairing, homologues may exchange chromosomal material at sites called chiasmata. In meiosis I, the homologues separate from each other, reducing the chromosome number to the haploid state (thus the reductive division). It is followed by a second division without replication, during which sister chromatids become separated. The result of meiosis I and II is four haploid cells. If sister chromatids separated at the first division, would meiosis still work?

Meiosis is characterized by the pairing of homologous chromosomes during prophase I. In many species, an elaborate structure called the synaptonemal complex forms between homologues. During this pairing, homologues may exchange chromosomal material at sites called chiasmata. In meiosis I, the homologues separate from each other, reducing the chromosome number to the haploid state (thus the reductive division). It is followed by a second division without replication, during which sister chromatids become separated. The result of meiosis I and II is four haploid cells. If sister chromatids separated at the first division, would meiosis still work?

Human Heredity: Principles and Issues (MindTap Course List)

11th Edition

ISBN:9781305251052

Author:Michael Cummings

Publisher:Michael Cummings

Chapter6: Cytogenetics: Karyotypes And Chromosome Aberrations

Section: Chapter Questions

Problem 19QP: The majority of nondisjunction events leading to Down syndrome are maternal in origin. Based on the...

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If sister chromatids separated at the first division, would meiosis still work?

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