![]() Homologous chromosomes are aligned along the metaphase plate. Pachytene: Chromosomes continue to shorten and thicken, and the synaptonemal complex becomes more noticeable.ĭiplotene: Centromeres of the paired chromosomes move apart.ĭiakinesis: Further condensation of chromosomes takes place. Zygotene: Homologous chromosomes start to pair up while condensing, and a close association called synapsis occurs between them. Leptotene: Chromosomes begin to condense, becoming visible. This stage is subdivided into five stages as: Furthermore, meiosis II also consists of five stages prophase II, metaphase II, anaphase II, and telophase II. Meiosis I has five stages, prophase I, metaphase I, anaphase I, and telophase I. Meiosis is composed of two cell divisions: meiosis I and meiosis II. Generally, telophase is followed by cytokinesis. Chromosomes also start to relax therefore, the condensation disappears. ![]() In the telophase, the nuclear membrane re-forms around each set of chromosomes and produces two distinct nuclei within the cell. Once the chromatids move to the spindle poles, the chromatids are referred to as chromosomes. Special proteins called molecular motor proteins disassemble tubulin molecules in the spindle and generate force so that chromosomes are pulled towards the opposite poles. In this phase, chromosomes are arranged along the center of the cell, metaphase plate as a single line.Īfter the metaphase connection between sister chromatids breaks down, the chromatids start to move in the opposite direction from each other, i.e., towards centrosomes. Then the other end of these microtubules gets attached to the centrosome of the opposite poles. Microtubules are attached to either side of the sister chromatids to kinetochores. Some spindle fibers are attached to the centromere regions of the chromosomes. Prometaphase starts with the degeneration of the nuclear membrane. ![]() However, this structure cannot be observed in some plant cells. The spindle grows out from a pair of centrosomes and grows towards the opposite end of the cell. At this stage, mitotic spindle microtubules move the chromosome within the cell forms. In this stage, chromosomes become more condensed and, therefore, can be seen under a light microscope. ![]() ProphaseĮach chromosome in a prophase cell consists of two sister chromatids attached to one centromere. Mitosis consists of five stages: prophase, prometaphase, metaphase, anaphase, and telophase and cytokinesis. – Comparison of Key Differences Key Terms In mitosis, a single nuclear division (karyokinesis) and cell division take place, whereas in meiosis, two nuclear and cell divisions take place (meiosis I and meiosis II). Both these processes denote the chromosome division followed by a cell division ( cytokinesis). The words mitosis and meiosis can be confused by some as they seem a bit alike. The main difference between mitosis and meiosis is that at the end of mitosis, the chromosome number in daughter cells is equal to the number in the original cell (mother cell), whereas, in meiosis, daughter cells receive half the number of chromosomes from the mother cell.
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