Centromeres

[Jules19]

Are centromeres always present, or do they assemble to hold sister chromatids together only at certains points in the cell cycle?

~Jules~

[HylaCinerea]

So long as the chromatids are held together in the "X" shape, the centromeres are present. That stated, they would be around in prophase and metaphase. However, the centromeres are broken right down the middle when the sister chromatids are pulled apart in anaphase.

[TheVirus]

That means they stay "broken" in the chromatids until the next duplication?

[HylaCinerea]

That was the term used when I studied it, yes. However, my book was likely not the best. If there is a more specific term, please do share.

[Jules19]

So after replication in the S phase, they're present again until anaphase of mitosis?

[andra]

Are u serious?what i know is centromere's a part of chromosome,and it will always be there,in all phases of cell cycle,but u said that it will break when the two chromatid sister apart,is it true?tell me more about it,i think for so long,what i know is wrong,tell me more bout,please

[TheVirus]

I think it only breaks in half and each half of the centromere stays with one of the chromatids, and then duplicates along with the rest of the chromosome during cell duplication, in order to be able to keep the new chromatid together with the old one.
I think i saw that in a book...

[andra]

U mean that each chromatid has one of the two break centromere!?

[TheVirus]

Yeah, but i'd rather someone else confirmed this, until i find that book. I'm not sure right now wheter it was talking about the centromeres or the centrioles...

[andra]

Yea,i think we talk about centriol,too,cz centriol will break too,are u agree with me?

[TheVirus]

no, centrioles don't break cause thay're not pulled apart during cell division, they just duplicate into two centrioles, do their work and each daughter cell keeps one of them for another division.

[andra]

Yea,u're right,centriol just dublicate and the two centriol will divide,and each daughter cell will keep it,
Well,may be now we can make a conclusion,that centromer will break when the chromatid sister separate,right?