Describe the processes of mitosis and meiosis in details and their functions
Introduction
Cell division does not stop with the formation of the mature organism but continues in certain tissues throughout life. It is because cell cannot grow any larger. Besides, cell division is necessary for the repair and replacement of aged or dead cells. Moreover, it is necessary for the growth and reproduction.
There are two distinct types of eukaryotic cell division: Mitosis and Meiosis. Mitosis leads to production of cells that are genetically identical to their parent and as the basis for producing new cells, whereas meiosis leads to production of cells with half the genetic content of the parent and as the basis for producing new sexually reproducing organisms. With these two types of cell division
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There are also five phases, including Interphase, Prophase, Metaphase, Anaphase and Telophase in meiosis. However, as there are two meiotic division, we usually divide the later four stages into part I and part II.
Interphase—DNA replication, the prelude to meiosis
The premeiotic S phase usually takes several times longer than a premitotic S phase.
Prophase I—further divided into leptotene, zygotene, pachytene, diplotene and diakinesis
Leptotene: chromosomes become visible in the light microscope and composed of paired chromatids.
Zygotene: Synapsis, process of chromosome pairing, caused the visible association of homologues with one another. It is accompanied by the formation of a complex called synaptonemal complex, a ladder-like structure with transverse protein filaments connecting the two lateral elements.
Pachytene: By the end of this stage, genetic recombination would be completed under the facilitation of enzymatic machinery from the recombination nodules, located within the center of the synaptonemal