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dumb question about chromosome/chromatid/homologous pairs

Discussion in 'DAT Discussions' started by ak47, Jun 3, 2008.

  1. ak47

    ak47 flossy flossy

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    so humans have 46 chromosomes
    Cliff's says that this is 23 homologous pairs for a total of 92 chromatids

    ?!?!?!

    thanks!
     
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  3. osimsDDS

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    yea thats right, Homologous pairs during meiosis are pairs of 2 so 2x23=46.
    Also since it is going through meiosis the cell has to duplicate 46 (46x2=92) to get 4 cells of haploid number 23. chromatids = single chromosomes while homologous pairs =pairs (x2).
     
  4. userah

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    23 homologous pairs means 46 chromosomes (one set from mother and one set from father) then each chromosome is made up of 2 chromatids; thus 46*2 = 92 chromatids total
     
  5. Hugh Mannity

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    Not in G1 or G0 however.
     
  6. osimsDDS

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    yea true because G1 the chromosomes dont replicate, thats before S phase, and if they dont have the right machinery or nutrients for replication it goes to G0....But I am pretty sure the person was talking about after S phase during prophase of M phase...
     
  7. gkhan

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    key thing to remember in meiosis is that there are 2 "cycles" and before meiosis II the chormatids do NOT duplicate.

    think of it like interphase->PMAT->MAT->4haploids
     

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