During anaphase, the chromatids of one of the chromosomes do not separate; they both move to one side of the cell. The two chromatids of the other chromosome do separate normally. Although you could...

Answer #8

Extracted text: During anaphase, the chromatids of one of the chromosomes do not separate; they both move to one side of the cell. The two chromatids of the other chromosome do separate normally. Although you could draw the nondisjoined chromosome moving in either direction (left or right), you draw it moving toward the left. This will make your answers to the questions below consistent with the grading key. Your anaphase drawing should show a cell that has two chromosomes on the left side of the cell. One of these chromosomes should have two chromatids and the other should have only one chromatid. The right side of the cell should contain a single chromosome with one chromatid. During telophase, the chromosome that failed to disjoin earlier has split. It is now two separate chromosomes. There should be three chromosomes on one side of the cell and one chromosome on the other side. All chromosomes should have one chromatid. Complete the drawings of telophase 5) Total number of chromosomes in cell A (bottom left cell) Normal cells have 46 chromosomes.) (Hint: 6) Total number of chromosomes in cell B (bottom right cell). 7) Number of chromosomes 21 in cell A (left). diploid, therefore have 2 chromosomes 21.) (Hint: Normal cells are 8) Number of chromosomes 21 in cell B (right) How many chromosome 21s are in cach of the two daughter cells that result from this nondisjunction? The cell with only one chromosome 21 will not survive. The other cell may survive and continue to divide. The process that you have just modeled shows how Down syndrome cells can arise as a normal fertilized egg grows and divides by mitosis.