In part species, cells go into a brief interphase, or interkinesis, before entering meiosis II. Interkinesis lacks one S phase, therefore chromosomes room not duplicated. The two cells created in meiosis i go with the occasions of meiosis II at the very same time. During meiosis II, the sister chromatids within the two daughter cell separate, forming four brand-new haploid gametes. The mechanics of meiosis II is similar to mitosis, other than that each separating cell has actually only one collection of homologous chromosomes. Therefore, each cell has fifty percent the number of sister chromatids to different out as a diploid cabinet undergoing mitosis.
You are watching: When does dna replication occur in meiosis
If the chromosomes decondensed in telophase I, they condensation again. If atom envelopes to be formed, they fragment into vesicles. The centrosomes the were replicated during interkinesis move away indigenous each other toward the opposite poles, and brand-new spindles space formed.
The nuclear envelopes are completely broken down, and also the spindle is totally formed. Each sister chromatid creates an individual kinetochore that attaches to microtubules indigenous opposite poles.
The sister chromatids space maximally condensed and aligned in ~ the equator the the cell.
The sister chromatids space pulled personally by the kinetochore microtubules and move towards opposite poles (Figure 1). Non-kinetochore microtubules elongate the cell.
In meiosis II, the connected sister chromatids staying in the haploid cells from meiosis I will be separation to type four haploid cells. The two cells produced in meiosis i go v the occasions of meiosis II in synchrony. Overall, meiosis II each other the mitotic division of a haploid cell. Throughout meiosis II, the sister chromatids space pulled personal by the spindle fibers and move toward opposite poles.
Telophase II and Cytokinesis
The chromosomes come at the opposite poles and begin to decondense. Atom envelopes form around the chromosomes. Cytokinesis separates the 2 cells right into four unique haploid cells. At this point, the newly formed nuclei room both haploid and have just one copy the the single collection of chromosomes. The cells produced are gene unique since of the random assortment the paternal and maternal homologs and because the the recombining the maternal and also paternal segment of chromosomes (with their sets that genes) that occurs throughout crossover.
The entire process of meiosis is outlined in number 2.
Meiosis II begins with the 2 haploid cells whereby each chromosome is made up of two linked sister chromatids. DNA replication go NOT take place at the beginning of meiosis II. The sister chromatids are separated, developing 4 genetically different haploid cells.
See more: Who Is Cooper Barnes Actor Abs, Cooper Barnes
Unless otherwise noted, pictures on this web page are license is granted under CC-BY 4.0 by OpenStax.
OpenStax, Biology. OpenStax CNX. May 27, 2016http://cnx.org/contents/s8Hh0oOc