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Now consider that microtubules are the organelle involved in mitosis (cell division) and the copying of genes!

A series of seventeen black and white sketches show observations of chromosomes in dividing cells. Many of the sketches do not show the outline of the cell, but instead just show mitotic spindles with attached chromosomes. Other sketches include the outline of the cell and the chromosomes. In the sketches of spindles, the spindle microtubules are lines that originate at opposite sides and meet in the middle. Chromosomes that are attached to the spindles resemble worms.
A series of seventeen black and white sketches show observations of chromosomes in dividing cells. Many of the sketches do not show the outline of the cell, but instead just show mitotic spindles with attached chromosomes. Other sketches include the outline of the cell and the chromosomes. In the sketches of spindles, the spindle microtubules are lines that originate at opposite sides and meet in the middle. Chromosomes that are attached to the spindles resemble worms.600×853 172 KB

Figure 1: Drawing of chromosomes during mitosis by Walther Flemming, circa 1880
This illustration is one of more than one hundred drawings from Flemming’s "Cell Substance, Nucleus, and Cell Division." Flemming repeatedly observed the different forms of chromosomes leading up to and during cytokinesis, the ultimate division of one cell into two during the last stage of mitosis.

© 2001 Nature Publishing Group Paweletz, N. Walther Flemming: pioneer of mitosis research. Nature Reviews Molecular Cell Biology 2, 72 (2001). All rights reserved.

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Figure 2: Types of microtubules involved in mitosis
During mitosis, several types of microtubules are active. The motor proteins associated with the interpolar microtubules drive the assembly of the spindle. Note the other types of microtubules involved in anchoring the spindle pole and pulling apart the sister chromatids.

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https://www.nature.com/scitable/topicpage/mitosis-14046258/