Metaphases I and II of meiosis are similar to mitotic metaphase. This event is due to the presence of kinetochore microtubules that pull these chromosomes back and forth.
During crossing over, the chromosomes of each pair are exchanged among each other.ĭuring metaphase, the chromosomes align at the equatorial plate of the cell. The Bouquet stage is where animal and plant chromosomes converge toward one side of the cell. Again, the nuclear membrane disintegrates, and the chromatin condenses. Prophase II will begin without undergoing interphase. The homologous chromosomes that comprise tetrads are not genetically identical because they came from two parents. Prophase I in particular is composed of five stages: leptotene, zygotene, pachytene, diplotene, and diakinesis.ĭuring prophase I, homologous chromosomes form a tetrad that is composed of four chromatids. Prophase in meiosis is relatively longer than in mitosis. The mitotic cell undergoes prophase only once. No interphase will happen before meiosis II.Īfter interphase, the cell proceeds to prophase, where the nuclear membrane disintegrates, and the chromatin condenses to form the chromosomes. It is only during the reproduction process that such a diploid state is restored in the offspring.īefore undergoing the four phases, the cell first needs to grow and replicate its chromosomes in a preliminary stage called interphase.Ī sex cell will only undergo interphase once. The chromosome number of the resulting daughter cells is reduced by half (becomes haploid, n). The resulting daughter cells are genetically the same because no recombination occurred during the process.įour. Two divisions results to haploid (n) offspring Only one division results to diploid (2n) offspring
Meiosis I and II have the same phases as mitosis, which are only different in some events. Meiosis is long as it involves two successive divisions that reduce chromosome number.īasically, it is divided into two: meiosis I and meiosis II. Mitosis involves only one cell division that is composed of four major phases: prophase, metaphase, anaphase, and telophase. In plants, sex cells are located in the pollen in the stamen and egg cells in the pistil. In animals like humans, meiosis takes place in male sperm cells and female egg cells to prepare them for sexual reproduction. Sexual division Meiosis occurs in sex cells or gametes. Somatic cells include muscle cells, bone cells, skin cells, nerve cells, etc. Somatic cells (or vegetative cells) are cells that make up the bodies of living organisms, other than the sex cells. Type of cell division and occurs in what type of cellsĪsexual division Mitosis occurs in somatic cells. Cell Division / Cellular Division/ Duplication Division/ Equational Division
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