Mitosis--kinetochores, kinetochore fibers, centrioles, centrosomes, centromeres, asters, and spindle

[whatwhy]

My book is so confusing that i have very little idea of what these do and how they go together. As I understand it, centrioles are in the centrosomes and during prophase the centrioles leave the centrosome and travel to opposite poles of the cell.

From here, I'm not really sure what goes on. There are spindle fibers that extend from the centriole, i think, but i dont know how asters fit in here. Then there are kinetochores that I think extend from the centromere, but im not sure what the kinetochore fibers are. The kinetochores link up with the asters on the centriole?

I dunno...please help! Thanks!

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[ElectricNoogie]

My book is so confusing that i have very little idea of what these do and how they go together. As I understand it, centrioles are in the centrosomes and during prophase the centrioles leave the centrosome and travel to opposite poles of the cell.

From here, I'm not really sure what goes on. There are spindle fibers that extend from the centriole, i think, but i dont know how asters fit in here. Then there are kinetochores that I think extend from the centromere, but im not sure what the kinetochore fibers are. The kinetochores link up with the asters on the centriole?

I dunno...please help! Thanks!

While this kind of detail is largely outside the scope of info required for the MCAT, if it helps you understand the process of cell division better then great. The aster is starshaped radial microtubules that surround the centrosomes. They aid in the migration/separation of chromosomes during cell division.

PROPHASE: 2 aster-covered centrosomes migrate to opposite sides of the nucleus in preparation of mitotic spindle formation.
METAPHASE: Kinetochore microtubules connect to the centromere.
ANAPHASE: Kinetochore microtubules pull the chromatids apart into individual chromosomes and pull them towards the centrosomes at the periphery.

All of this allows the cell to divide properly with each daughter cell containing full complements of chromosomes.