Question

If you were told that you would get extra credit for finding a model showing chromosomes separating while sister chromatids were still attached, you would look for a model of:

a) Prophase I
b) Prophase II
c) Anaphase I
d) Metaphase I
e) Anaphase II

Answer 1

For a model depicting chromosomes separating while sister chromatids are still attached, you should look for anaphase I of meiosis. This phase features homologous chromosomes moving apart with sister chromatids intact, in contrast to anaphase II where sister chromatids separate.

Step-by-step explanation:

If you were told that you would get extra credit for finding a model showing chromosomes separating while sister chromatids were still attached, you would look for a model of anaphase I. During anaphase I, the pairs of homologous chromosomes are pulled apart and migrate towards the poles, but the sister chromatids remain attached to each other. This is unlike anaphase II, where the sister chromatids separate and move to opposite poles. Hence, anaphase I accurately represents the stage where chromosomes are separating while the sister chromatids are still attached.

In contrast, during metaphase I, the chromosomes appear in homologous pairs on the spindle but are not yet separating. Metaphase II involves a single line of chromosomes on the spindle, and it is the stage before the sister chromatids separate. In summary, for your extra credit assignment in cell division and the stages of meiosis, anaphase I is the phase you would be interested in demonstrating.