Sometimes there is an interkinesis phase, a small period of rest after meiosis I. Meiosis Iīefore the start of meiosis I, DNA replication happens during interphase or the cell growth stage of the cell cycle.īefore meiosis II there is no interphase or DNA duplication as there is before meiosis I. The table below highlights key differences between the two parts of meiosis (Table 1). Meiosis II is the second part of meiosis and follows meiosis I. Differences between meiosis II and other types of cell division Meiosis II and meiosis I: differences The cleavage furrow is the point at which the cytoplasm starts to pinch inward in preparation for cytokinesis, which is division of the cytoplasm.Īt the end of cytokinesis and telophase II of meiosis II, four haploid daughter cells remain.įigure 3: The cells during anaphase II and telophase II of meiosis II. Therefore, crossing over would not be as beneficial in this stage of meiosis and does not occur. Since homologous chromosomes are now in separate cells, only sister chromatids, which include one original chromatid and its copy, remain. It is important to note that, in prophase II of meiosis II, crossing over does not occur.
The chromosomes condense to prepare for movement to opposite poles of the cell.Centrosomes (in animal cells) migrate to opposite poles of the cells.Prophase II of meiosis II:ĭuring prophase II, as in mitosis and meiosis I, the following steps occur: In the following explanation of each stage in detail, you will see that meiosis II shares more similarities with mitosis than meiosis I did, except for the reduced chromosome number.įigure 1: An overview diagram of meiosis. They are as follows:īoth daughter cells produced at the end of meiosis I will go through these stages, resulting in four haploid daughter cells, or gametes. The stages that make up meiosis II are the same as those in meiosis I and mitosis, except that they contain the roman numeral "II" after each stage. However, no DNA duplication events occur during this time. Interkinesis is a small period of rest that some cells may go through between meiosis I and meiosis II. Some cells may go through a brief period between these two parts of meiosis called interkinesis. This means that after meiosis I the two daughter cells do not re-enter interphase and no duplication event occurs between meiosis I and meiosis II. How do we define meiosis II?ĭirectly after meiosis I, the two haploid daughter cells with extra chromosome copies undergo meiosis II, so that the sister chromatids, or identical chromosome copies, can be split evenly to produce four haploid daughter cells (Fig. Following directly after meiosis I, meiosis II produces four haploid daughter cells, known as gametes. Meiosis II is the s econd round of cell division in the process of meiosis, or the creation of gametes (sex cells). If you haven't had the chance, go check out our article on m eiosis I before delving into this next big topic! If you started this article by first reading about meiosis I, then you are expecting the next step in the journey of meiosis.
The best things in life come in pairs: best friends, milk and cookies, and meiosis I and meiosis II.
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