Mitosis

By Vicky

    The Mitosis has seven phases in which it makes two daughter cells and those daughter cells come from a single parent cell. Mitosis has many phases, such as, Prophase, Metaphase, Anaphase, Telophase, Interphase, Prometaphase, and Cytokinesis. Each of these phases have a process in which something is created. As you can see in the picture above, the first phase is Interphase. Interphase is when many cellular organelles double or as we say, the DNA replicates, and protein synthesis occurs. Protein Synthesis is the process where DNA seals for the production of amino acids and proteins. In this process, we see 46 chromosomes, 23 from each parent.

In the second phase of Mitosis, Prophase, the chromatin condenses into a chromosome(s). After this happens, the chromosomes are duplicated and two sister chromosomes are made. Prometaphase is the next phase of mitosis where the middle inside of the cell disrupts, but its vesicles remains visible. Then, kinetochores, attachment points for chromosomal microtubules, mature and attach to some of the spindle microtubules.

    Metaphase, the fourth phase of Mitosis, is when  all the chromosomes are aligned in the metaphase plate. This process takes time because the alignment of the chromosomes must be correct. Http://www.accessexcellence.org states that Metaphase is when , "The chromosomes align at the equatorial plate and are held in place by microtubules attached to the mitotic spindle and to part of the centromere."

     Anaphase, the third to last phase of Mitosis, is when the chromatids that are now known as chromosomes, separate. Anaphase is, "The centromeres divide. "Sister chromatids separate and move toward the corresponding poles," says www.accessexcellence.org. At the end of this phase, a complete set of chromosomes have been structured at each pole of the cell and as you can see in the picture, the chromosomes are being pulled apart.

Telophase is when the chromosomes  are now  splitting into two and  the cell division starts.Telophase is, "Daughter chromosomes arrive at the poles and the microtubules disappear. The condensed chromatin expands and the nuclear envelope reappears. The cytoplasm divides, the cell membrane pinches inward ultimately producing two daughter cells (phase: Cytokinesis)," www.accessexcellence.org explains.

    Last but not least, Cytokinesis is when the actual cell division happens.  This works because the actin filaments in the middle of the cell help divide it. Although there are many different phases in Mitosis, they are all important because if one phase is missing then Mitosis couldn't happen.

    Walter Flemming  was one of the few people who helped with the finding of Mitosis. He was  the first person to study chromosomes and the division of cells (salamander larvae in the 1880s). Walter Flemming studied Mitosis in the 1880s and used live imaging (to take pictures of Mitosis) in the 1920s-1950s.In 1879, Walter Flemming observed how chromosomes work as cells divide and multiply.

 Resources:

1.http://www.ba-education.demon.co.uk/dna/mitosis.jpg

2.http://www.phschool.com/science/biology_place/biocoach/meiosis/anai.html

3.http://www.accessexcellence.org/RC/VL/GG/mitosis.html

4.Life science Lab Book

Click here to get a great animation of Mitosis

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Click here to get a awesome video of mitosis