Tuesday, August 15, 2006

Cytogenetics again?! Mitosis

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This is another book I want to buy.. but not so soon la.. kinda broke wei.

Hmm, started to appreciate the chromosomes.. Indeed, science is a tool to discover the wonders of God. You just can't stop praising Him, so amazed at the work of His hands.

Here at some of the mitotic phases. All these photos are from
http://micro.magnet.fsu.edu/micro/gallery/mitosis/mitosis.html

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This is the interphase of cell cycle, before mitosis. It is not part of mitosis. where the cell is at its resting stage. The chromosomes are diffused, fine threads.


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This is late prophase where the chromosomes are condensed and thicken.



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This is metaphase of mitosis. The colour is due to the staining reagents they use to identify the structures. The blue colour thingy are the chromosomes. The green colour thingy is the spindle fiber. The spindle fibers are actually bundles of microtubules. The microtubules are connected to the kinetochore at the centromeres of the chromosomes. When the microtubules depolymerize(shortens), it will pull apart the 2 sister chromatids of a single chromosome.


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This is anaphase of mitosis in the root tips of onion, Allium cepa. The microtubules depolymerise and pull the sister chromatids apart to the opposite pole.



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This is telophase. The two sets of chromosomes are at the opposite pole, having the same genetic material.

Cytokinesis takes place and forms 2 daugther cells. Different mechanisms of cytokinesis are found in plant cells and animal cells.

This is the process that occurs in every cell of your body.

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