Simple question about Mitosis

[UCSD1984]

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According to Cliff's AP Bio...

After Mitosis, the number of CHROMOSOMES in each daughter nucleus is 46, and the number of CHROMATIDS in each daughter nucleus is also 46.

I understand the number of chromosomes being 46, but shouldn't there be 92 chromatids in the daughter nucleus? I'm envisioning 46 chromosomes as 2 connected sister chromatids.

Could someone clarify this for me?

Edit: It's page 78 in Cliff's.

 

[Demps]

NOORALLAH just asked the same question. Here we go

http://faculty.clintoncc.suny.edu/f...io 101/bio 101 laboratory/mitosis/mitosis.htm

 

[UCSD1984]

NOORALLAH just asked the same question. Here we go

http://faculty.clintoncc.suny.edu/f...io 101/bio 101 laboratory/mitosis/mitosis.htm

That's a great site, thanks. So it says during G1, "the chromosomes have 1 chromatid", and it's not until after the S-phase/during G2 where the chromosomes are now replicated and have 2 chromatids per chromosome.

So my question now is this; Is it safe to say that the "46 chromosomes and 46 chromatids in each Mitotic daughter nucleus" summary of Mitosis in Cliff's is referring to pre-S-Phase?

 

[Demps]

That's a great site, thanks. So it says during G1, "the chromosomes have 1 chromatid", and it's not until after the S-phase/during G2 where the chromosomes are now replicated and have 2 chromatids per chromosome.

So my question now is this; Is it safe to say that the "46 chromosomes and 46 chromatids in each Mitotic daughter nucleus" summary of Mitosis in Cliff's is referring to pre-S-Phase?

Yes I think you are right.
Read the first post that I put on NOORALLAH's question.

 

[SEAirLand]

That's a great site, thanks. So it says during G1, "the chromosomes have 1 chromatid", and it's not until after the S-phase/during G2 where the chromosomes are now replicated and have 2 chromatids per chromosome.

So my question now is this; Is it safe to say that the "46 chromosomes and 46 chromatids in each Mitotic daughter nucleus" summary of Mitosis in Cliff's is referring to pre-S-Phase?

Correct. Chromosome applies to either situation (pre-S or post-S) and is regardless of the number of chromatids.

Pre-S = 46 Chromosomes, 46 Chromatids.
Post-S = 46 Chromosomes, 92 Chromatids.

 

[UCSD1984]

Perfect. Thank you guys, I appreciate it. That link you provided is a great site to go to for review of this chapter. I always hated the cell cycle and molecular bio. I'd much rather be memorizing evolution and taxonomy, as weird as that sounds.

 

[Demps]

Perfect. Thank you guys, I appreciate it. That link you provided is a great site to go to for review of this chapter. I always hated the cell cycle and molecular bio. I'd much rather be memorizing evolution and taxonomy, as weird as that sounds.

Glad I could help man. Good luck!