A karyotype is a physical representation (usually a photograph) of all of the chromosomes in a single cell; however, the cell must be in mitotic metaphase when the karyotype is made. Why?
a) Metaphase is the only stage of the cell cycle in which both sets of homologous chromosomes are present in the cell.
b) Metaphase is the only stage of the cell cycle in which the cell membrane is permeable to dye.
c) Metaphase is the only stage of the cell cycle in which single chromosomes move toward the poles.
d) Metaphase is the only stage of the cell cycle in which the chromosomes have condensed and aligned, but have not yet separated.
e) Metaphase is the only stage of the cell cycle in which both sister chromatids of each chromosome are present in the cell.
Answer: d) Metaphase is the only stage of the cell cycle in which the chromosomes have condensed and aligned, but have not yet separated.