00:02
Problem 13 says a cell has 38 chromosomes.
00:05
After mitosis and cell division, one daughter cell has 39 chromosomes and the other has 37.
00:11
What might have caused these abnormal chromosome numbers? what effects do you suppose this might have on cell function and why? so normally in mitosis, the cell would have identical numbers of chromosomes to the parent cell.
00:23
So both daughter cells in this case should have had 38, but for some reason one got an extra and one has one too few.
00:30
And so this disorder or this abnormal number of chromosomes is actually referred to as aneuploity.
00:39
If you break down the latin or greek origins of that word, it basically means being without a good fold.
00:45
And so in this case, for some reason, these chromosomes were not separated correctly.
00:51
And so that can be due to a number of issues.
00:55
And so for some reason, these chromosomes actually ended up in an abnormal amount.
00:59
And so the primary cause of this is when homologous chromosomes actually fail to separate.
01:06
And so when these chromosomes line up in the middle of the cell during metaphase, the spindle fibers attached to the centrioles actually pull these chromosomes apart to opposite ends of the cell to become two new cells.
01:18
And for some reason in this case, it's likely that one of these homologous chromosomes actually didn't separate and just stayed as a paired chromosome in one cell versus the other...