Answer:
Prophase:
The genetic material, chromatin (DNA), condenses to form highly organized structures, the chromosomes. The genetic material has been previously duplicated during the S phase of the Interface, now the replicated chromosomes are formed by two chromatids, joined by the centromere by cohesin molecules.
The centrosome is doubled and the two child centrosomes (each with two centrioles) migrate to opposite ends of the cell. Centrosomes are microtubule organizing centers, controlling their formation by polymerizing soluble tubulin. The spindle of a mitotic cell has two poles that emanate microtubules.
The nucleolus disappears and the nuclear envelope is disorganized.
In the prometaphase the nuclear envelope has dissolved. The microtubules invade nuclear space and can anchor chromosomes through the kinetochors. They can also interact with microtubules emanating from the opposite pole. The nuclear envelope separates and the microtubules invade the nuclear space.
Each chromosome assembles two sister cinetocoros on the centromere, one in each chromatid. When a microtubule is anchored to a kinetochore, motor proteins that use energy from ATP hydrolysis are activated to "ascend" through the microtubule toward the centrosome of origin. This activity coupled with the polymerization / depolymerization of the microtubules, provides the necessary pushing force to further separate the two chromatids from the chromosomes.
Metaphase: The centromeres of the chromosomes congregate in the "metaphase plate" or "equatorial plane," an imaginary line that is equidistant from the two centrosomes found in the 2 spindle poles. This balanced alignment in the middle line of the spindle is due to the equal and opposite forces that are generated by the brother cinetocoros.
Correct chromosomal separation requires that each kinetochore be associated with a set of microtubules.
Anaphase: When all the chromosomes are correctly anchored to the spindle microtubules and aligned in the metaphase plate, the cell proceeds to enter an anaphase. It distributes the two copies of the original genetic information.
Then the proteins that held together both sister chromatids (the cohesins), are cut, which allows the separation of the chromatids. These sister chromatids, which are now different sister chromosomes, are separated by microtubules anchored to their kinetochromes when disassembled, heading towards the respective centrosomes.
Then the microtubules not associated with kinetocoros lengthen, pushing the centrosomes (and the set of chromosomes that have associates) towards the opposite ends of the cell.
These two states are sometimes called early anaphase and late anaphase. The early anaphase is defined by the separation of sister chromatids, while the late one by the elongation of the microtubules produced by the separation of the centrosomes. At the end of the anaphase, the cell has managed to separate two identical sets of genetic material, each around a centrosome.
Telophase: During telophase, microtubules not bound to cinetocoros continue to lengthen, further stretching the cell. The sister chromosomes are each associated to one of the poles. The nuclear envelope is reformed around both chromosomal groups. Both sets of chromosomes, now forming two new nuclei, are decondensed again in chromatin. Caryokinesis is over, but cell division is not yet complete.
The next step is cytokinesis, where the final division of daughter cells occurs.
To make the mitosis process more graphic, i attach an explanatory graph.
