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:. What is a stem cell? What is a cell? What is DNA? What is a chromosome? What is a genetic disorder? What is meiosis? Mitosis versus meiosis. How helpful was this page? Chromosomal Abnormalities: Aneuploidies. Chromosome Abnormalities and Cancer Cytogenetics. Copy Number Variation and Human Disease.
Genetic Recombination. Human Chromosome Number. Trisomy 21 Causes Down Syndrome. X Chromosome: X Inactivation. Chromosome Theory and the Castle and Morgan Debate. Developing the Chromosome Theory. Meiosis, Genetic Recombination, and Sexual Reproduction. Mitosis and Cell Division. Genetic Mechanisms of Sex Determination. Sex Chromosomes and Sex Determination. Sex Chromosomes in Mammals: X Inactivation.
Sex Determination in Honeybees. Citation: O'Connor, C. Nature Education 1 1 The five phases of mitosis and cell division tightly coordinate the movements of hundreds of proteins.
How did early biologists unravel this complex dance of chromosomes? Aa Aa Aa. Mitosis Occupies a Portion of the Cell Cycle. Figure 2. Figure 1. Figure Detail. Figure 3. Ascaris megalocephala bivalens, as drawn by Boveri in The figure shows chromosomes in the middle of the dividing cell, as well as the spindle, two centrosomes, and two centrioles within each centrosome. Note that the cytoplasm is perceived as being structured.
Figure 6. Figure 5. Figure 7. Figure 8. Figure Telophase and Cytokinesis. References and Recommended Reading Cheeseman, I. Article History Close. Share Cancel. Revoke Cancel. Keywords Keywords for this Article. Save Cancel. Flag Inappropriate The Content is: Objectionable. Flag Content Cancel. Email your Friend. Submit Cancel. This content is currently under construction.
Explore This Subject. Chromosome Analysis. Chromosome Structure. Mutations and Alterations in Chromosomes. Chromosome Number. Chromosome Theory and Cell Division. Sex Chromosomes. Topic rooms within Chromosomes and Cytogenetics Close. No topic rooms are there. Or Browse Visually. Other Topic Rooms Genetics. Student Voices. Creature Cast. The stages of mitosis are: prophase, metaphase, anaphase and telophase. Only two pairs of chromosomes are shown in the diagrams below. There are 23 pairs of chromosomes in a diploid human body cell.
The stages of mitosis in detail Mitosis is a type of cell division in which a diploid body cell copies itself and finally divides into two identical diploid daughter cells. The stages of the cell cycle are: Stage What happens Interphase The cell spends most of its life in this phase.
The DNA in chromosomes copies itself ready for mitosis. Prophase The DNA in chromosomes and their copies condenses to become more visible.
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