During anaphase I the sister chromatids move together to the same pole. During anaphase II the sister chromatids are separated to opposite poles. Similarities Mitosis Diploid parent cell Consists of interphase, prophase, metaphase, anaphase and telophase In metaphase individual chromosomes pairs of chromatids line up along the equator.
Ends with cytokinesis. Meiosis Diploid parent cell Consists of interphase, prophase, metaphase, anaphase and telophase but twice! In metaphase II individual chromosomes pairs of chromatids line up along the equator.
Related Content:. What is mitosis? What is meiosis? What is a cell? What is a stem cell? Meiosis is the type of cell division that creates egg and sperm cells.
Mitosis is a fundamental process for life. During mitosis, a cell duplicates all of its contents, including its chromosomes, and splits to form two identical daughter cells. Because this process is so critical, the steps of mitosis are carefully controlled by certain genes. When mitosis is not regulated correctly, health problems such as cancer can result.
The other type of cell division, meiosis, ensures that humans have the same number of chromosomes in each generation. It is a two-step process that reduces the chromosome number by half—from 46 to 23—to form sperm and egg cells.
When the sperm and egg cells unite at conception, each contributes 23 chromosomes so the resulting embryo will have the usual Mitosis is divided into five phases: 1.
Interphase: The DNA in the cell is copied in preparation for cell division, this results in two identical full sets of chromosomes. Outside of the nucleus are two centrosomes, each containing a pair of centrioles, these structures are critical for the process of cell division. During interphase, microtubules extend from these centrosomes. Prophase: The chromosomes condense into X-shaped structures that can be easily seen under a microscope.
Each chromosome is composed of two sister chromatids, containing identical genetic information. The chromosomes pair up so that both copies of chromosome 1 are together, both copies of chromosome 2 are together, and so on.
At the end of prophase the membrane around the nucleus in the cell dissolves away releasing the chromosomes. The mitotic spindle, consisting of the microtubules and other proteins, extends across the cell between the centrioles as they move to opposite poles of the cell. Metaphase: The chromosomes line up neatly end-to-end along the centre equator of the cell.
The centrioles are now at opposite poles of the cell with the mitotic spindle fibres extending from them. The mitotic spindle fibres attach to each of the sister chromatids. Anaphase: The sister chromatids are then pulled apart by the mitotic spindle which pulls one chromatid to one pole and the other chromatid to the opposite pole.
Telophase: At each pole of the cell a full set of chromosomes gather together. A membrane forms around each set of chromosomes to create two new nuclei. The single cell then pinches in the middle to form two separate daughter cells each containing a full set of chromosomes within a nucleus. This process is known as cytokinesis. Related Content:.
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