Video Transcript
Meiosis is a form of cell division. There are two divisions of meiosis, I and II. Which of the following is the correct order of stages in division II, as shown in the diagram? (A) Metaphase II, anaphase II, telophase II, prophase II. (B) Anaphase II, telophase II, prophase II, metaphase II. (C) Prophase II, metaphase II, anaphase II, telophase II. (D) Prophase II, anaphase II, metaphase II, telophase II. (E) Interphase II, prophase II, metaphase II, anaphase II.
Meiosis is a form of cell division that produces gametes for sexual reproduction. There are two separate divisions in meiosis called meiosis I and meiosis II. The provided figure shows the steps of meiosis II.
We start with two copies of 23 chromosomes, or 46 in total. Before meiosis I, a step called interphase takes place, where each of these 46 chromosomes duplicate. Then, in meiosis I, one copy of each duplicated chromosome is separated into a new cell. Now there are two cells, and each cell has 23 duplicated chromosomes. You can see these two cells here.
Next, we can enter meiosis II. In meiosis II, the duplicated chromosomes from each of these two cells are separated to single chromosomes. By the end of meiosis II, there are four cells as indicated here, which are the gametes. The stages of meiosis II are analogous to meiosis I. Let’s describe these stages to determine the answer to this question.
In the first stage of meiosis II, called prophase II, spindle fibers reposition in the cell. In the next stage, called metaphase II, the duplicated chromosomes are pulled to the cell’s equator by the spindle fibers. In anaphase II, each chromatid of the duplicated chromosome is separated by the spindle fibers. In the final step, called telophase II, two nuclei form and the two cells separate to form four cells, each with a single chromosome.
So now that we have the correct sequence for meiosis II, we can see that the best option is given by answer choice (C): prophase II, metaphase II, anaphase II, telophase II.