What Do Chromatids Do?
what do chromatids do?
Josh P. The Gratifying Blog Of The Necromancer: Meiosis
In Meiosis there are alot of certain things that are different than Mitosis. Mitosis is for cell reproduction and each cell is made exactly the same. In Meiosis genes and traits are the difference. No two things created by Meiosis are exactly the same and this is very interesting. It makes sure that nothing is the same. That makes flowers the way they are, people the way we are, and animals the way they are. There are also 5 main steps in Meiosis but you'll see the difference is my explanations and diagram below.
Frequencies of chromosomal aberrations and sister chromatid exchanges in the benthic worm Neanthes arenaceodentata exposed to ionizing radiationLearn more
Florence Louise Montana Harrison
Prophase I
Nuclear division is about to occur in the first phase. A spindle forms as centrosomes move away from each other. The nucleolus disappears and so do the nuclear envelope fragments. Homologous chromosomes both have two sister chromatids and have to go through synapsis to make bivalents. The exchange of color may occur over the nonsister chromatids After this happens the sister chromotids are no longer identical.
Metaphase I
The bivalents held together by chiasmata have moved towards the equator of the spindle. This is determined by a fully formed spindle and alignment of the bivalents at the equator of the spindle.
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Icon Group InternationalProtein complexes on the outside of the centromeres are called Kinetochores and should be seen by now. These are attached to spindle fibers. The bivalents align themselves at the equator of the spindle. Then the maternal and paternal homologues may be oriented on either pole. This means that all possible combinations can occur in the daughter cells.
Anaphase I
The homologues of each bivalent seperate and move to opposite poles. Each chromosome still has two chromatids.
Telophase I
Creates divisions so that each daughter cell has one chromosome from each homologous pair. Each parent has two pairs of homologous pairs of chromosomes. After telophase we get into Interkinesis. This is when mitotic division is similar to Interphase except DNA replication does not occur because chromosomes are already duplicated.
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