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I need help writing a simple and original answer.Mitosis and meiosis are similar processes, but they have some very important differences. Explain how mitosis and meiosis are alike and how they are different. Provide at least two similarities and three differences.

User Junle Li
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Mitosis and meiosis are both processes of cell division.

During mitosis, the cell divides and forms two diploid daughter cells identical to the mother cell.

During meiosis, the cell divides into four haploid cells, different from the mother cell.

Mitosis

The phases of mitosis are the following:

Prophase: During this phase, the chromatin condenses into chromosomes, the nuclear membrane breaks down, the centrioles start to move to the polar sides of the cell and the spindle starts to form between them.

Metaphase: during this phase, the spindle fibers attach to the centromere of each sister chromatid and the sister chromatids line up in the equator of the cell.

Anaphase: during this phase, the sister chromatids separate and the centromeres divide. The sister chromatids are pulled apart by the spindle and each one moves towards one pole of the cell.

Telophase: during this phase, a new nuclear membrane is formed, the chromosomes uncoil to form chromatin, and the spindle breaks down.

After the telophase, cell division itself occurs, this phase is called cytokinesis, during this phase, a ring of microfilaments form around the equator of the cell, this ring starts to close inward around the equator until two daughter cells are formed.

Meiosis

As mentioned before, meiosis is also a process of cell division, the difference is that the cell divides not one by two times.

The first division is called Meiosis I and has the phases: Prophase I, Metaphase I, Anaphase I, Telophase I, and cytokinesis, these phases are quite different from the phases of mitosis.

Prophase I: this phase is almost equal to the prophase of mitosis with the difference that during this phase the homologous chromosomes form pairs and exchange genetic information during a process called cross-over.

Metaphase I: in this phase, instead of the sister chromatids, it is the homologous chromosomes that line up in the equator of the cell.

Anaphase I: each chromosome of the homologous pair separates and moves towards one of the poles of the cell as the spindle fibers shorten.

Telophase I: The spindle breaks down, and new nuclear membranes form.

Cytokinesis: The cytoplasm of the cell divides formin two haploid daughter cells.

After meiosis I, the cells go on to the second division, called meiosis II.

Is important to remember that between meiosis I and meiosis II there is no DNA replication.

Meiosis II

Meiosis II has 5 phases called: prophase II, metaphase II, anaphase II, telophase II, and cytokinesis.

The phases of meiosis II and mitosis are equal, with the difference that after meiosis II two haploid daughter cells form:

Prophase II: Nuclear membrane breaks down, the centrioles start to separate, and the spindle begins to form in each sister chromatid.

Metaphase II: The spindle fibers line up the sister chromatids in the equator of the cell.

Anaphase II: The sister chromatids separate and move to the poles of the cell.

Telophase II: The spindle breaks down and a new nuclear membrane is formed.

Cytokinesis: the cytoplasm of the cell divides. At the end of this phase, four haploid cells with unique chromosome combinations are formed.

User Rohith Nandakumar
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