The non-kinetochore microtubules are lengthened in order to push the chromosomes further apart. Homologous chromosomes are separated from the cohesin at the arms of the chromosomes. Each separated bivalent chromosome starts moving towards the opposite poles due to the tension generated by the microtubules. Anaphase 1 is followed by telophase 1 where the bivalent chromosomes arrive at the opposite poles. The first division of the cytoplasm is initiated at the anaphase 1. Figure 1: Phases of Mitosis.
Anaphase 2, which takes place at the meiosis 2, is the step where sister chromatids are separated. Metaphase 2 is followed by anaphase 2. During metaphase 2, two kinetochore microtubules, each from two opposite poles, are attached to the same centromere of the individual chromosomes.
The proper arrangement of the individual chromosomes at the equatorial plate, binding with the kinetochore microtubules lets the cell to proceeds into the anaphase 2. During anaphase 2, the centromeric cohesion protein complexes are cleaved due to the contacting tension of the kinetochore microtubules on the centromere of the each individual chromosome.
Thus, the bivalent chromosomes are separated into two sister chromatids. Each sister chromatid is now known as a daughter chromosome. Further contraction of the kinetochore microtubules pulls each daughter chromosome towards the opposite poles. Anaphase 2 is followed by the telophase 2 where the formation of the haploid nuclei at the opposite poles is taken place.
Anaphase 1: Anaphase 1 takes place during meiosis 1. Anaphase 2: Anaphase 2 takes place during meiosis 2. Anaphase 1: Anaphase 1 occurs in diploid cells. Anaphase 2: Anaphase 2 occurs in haploid cells. Anaphase 1: Two spindle fibers are attached to the centromere of the each chromosome in the homologous pair. Anaphase I takes place in diploid cells and its aim is to produce the cells having half the number of chromosomes.
The sister chromatids of each chromosome remain attached during anaphase I. Division of the centromere also does not happen during anaphase I. At the end of anaphase I, each pole attains one homologous chromosome which will then go to each daughter cell. Anaphase II is the third step in the meiosis II in which the sister chromatids are being segregated.
This phase takes place in haploid cells which are formed as a result of meiosis I. During this phase, each homologous chromosome is joined by spindle fibers by the opposite poles which exert force and pull the sister chromatids towards opposite sides.
Finally, centromeres of each chromosome are split, chromatids are being separated and go to the opposite pole. Later, these chromatids are arranged to form chromosomes. In this step, the arrangement of chromatids is rotated to the angle of ninety degrees from that of anaphase I. This step resembles with the anaphase of mitosis because the number of chromosomes remains the same after the division. Both anaphase I and anaphase II are the phases of meiosis which is the part and parcel of sexual reproduction in human beings and other animals.
It is very important for biology students to know the differences between anaphase I and anaphase II. In the above article, we came across the clear differences between anaphase I and anaphase II. Save my name, email, and website in this browser for the next time I comment.
Ecology Microbiology Science. In anaphase 1 in meiosis , homologous pairs are separated but sister chromatids stay joined together. In anaphase 1 of mitosis the sister chromatids do separate.
Meiosis each homologous pair moves to the pole. The centromere does not divide. Mitosis only one chromatid of each chromosome moves to the pole. Chromatids moving to one pole are identical genetically to the ones moving to the opposite pole. What is the difference between anaphase 1 in meiosis and anaphase in mitosis?
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