Meiosis is a process of cell division that only happens in eukaryotes. Eukaryotes are organisms that are membrane bound. Meiosis is seen to happen after spore production for plants, while meiosis is seen to happen during gamete formation for animals. In addition, the result of this process results in having daughter cells. The parent cell divides and produces the four gametes. This process is also known as a reduction division because it produces four haploids.
This process has two stages, meiosis I and meiosis II. There is a preparatory phase, also known as interphase, where the parent cell produces more DNA and proteins, resulting in a bigger cell size and mass. Then the dividing cell replicates its chromosomes, which allows the parent cell to enter the first stage of meiosis. Both two stages of Meiosis, each has 4 phases that has its own important step to contribute.
There are four phases of Meiosis I. The first phase is Prophase I, where the chromosomes condense and move towards the nuclear envelope. Spindle fibers also form in this phase and the process of crossing over. The second phase is Metaphase I, where the homologous chromosomes pair up in the equatorial plane in the center of the cell. The centromeres are found in the opposite poles in this phase. The third phase is Anaphase I, where the chromosomes move to the opposite poles of the cell. The sister chromatids aren’t separated yet and still intact. The fourth phase is Telophase I, where the chromosomes move towards the poles, which have haploid number of chromosomes. In this phase, condensation and cytokinesis occurs. The nuclear envelope also forms which results in two daughter cells with haploid chromosomes.
The second stage is Meiosis I, which also has four stages. The first phase in this stage is Prophase II, where the chromosomes are in the process of moving to the equatorial plane. In this phase, the nuclei and nuclear membrane are also separated. The second phase is Metaphase II, where the chromosomes are already aligning in the equator and the centromeres move towards the opposite poles. The third phase is Anaphase II, where the sprindle fibers separates the sister chromatids. The fourth phase is Telophase II, which is the last process that produces the four daughter cells/gametes. The four nuclei produces allows for the development of a nuclear envelope. The four daughter cells produces are all haploid, which means that they have half the number of chromosomes.