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The anaphase it is one of the stages of the mitosis and of the meiosis , two methods of cell reproduction. In the anaphase the separation of pairs of chromosomes that are homologous .

In this instance, therefore, the chromatids (the units of the chromosome that has already doubled) move towards the opposite sector of the cell through the achromatic spindle , composed of various microtubules arising from the centrioles within the framework process .

Mitosis takes place in the nucleus of eukaryotic type cells to distribute, in an equitable way, genetic information. Anaphase is the stage that follows the interface , the prophase , the promethaphase and the metaphase , in that order. It starts from the regulation of proteins while the transition between metaphase and telophase (the instance that continues to anaphase).

Anaphase in mitosis

When the anaphase begins in mitosis, the sister chromatids separate completely and move in the direction of the poles opposites of the cell that is being divided. In this context the cinetocoro , a protein complex that can be considered the fundamental point that contacts chromosomes with microtubules; the cinecotoro goes through an assembly process in each centromere.

The microtubules that are in charge of contacting the cinecotoro are known as K fibers ; they consist of certain proteins, such as tubulin, and their function in this case it is progressively shortened to transport the chromatids to the corresponding cell pole.

Another of the phenomena What can be seen at the beginning of anaphase in mitosis is the regulation of transition proteins that takes place from metaphase. When the time comes, the promtor complex is activated and the cyclin that kept the metaphase running is deactivated. Also, the deactivation of the protein called occurs securina , which inhibits the protease called separase; the latter can then separate the protein cohesin, which is responsible for maintaining the union between the two chromatids, and it is here that the anaphase itself is considered to begin.

In the anaphase of mitosis one can distinguish between the early anaphase (where the separation of the chromatids by action of the kinetocoros and the shortening of the achromatic spindle is recorded) and the late anaphase (The fibers, after complete separation of the chromatids, are shortened further so that said chromatids reach the poles of the cells ).

Anaphase in meiosis

Throughout meiosis, we can find the anaphase I and the Anaphase II , although there are also successive divisions : the first consists of prophase I, metaphase I, anaphase I and telophase I, while in the second, prophase II, metaphase II, anaphase II and telophase II take place.

During anaphase I, the separation of the centromeres begins because of the attraction that the poles exert on them, and each one is dragging in its path to the two chromatids that have joined. For bivalent or homologous chromosomes in which there are no chiasmas (the cross-linking of structures organic, in this case non-sister chromatids), separation is simply given; On the other hand, when there are chiasmas, the chromosomes move forward to the chromosomal ends.

It is important to note that we can see a similarity between the anaphase of meiosis and what takes place in mitosis, specifically when the centromere children separate and take chromatids to the poles (also known as chromatidia, are the two filaments that make up the chromosome ).

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