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Meiosis Vs Meitosis

More than one celled organisms grow by way of mitosis and the cytoplasmic division of body cells. On the other hand, meiosis occurs only in germ cells, which are put aside for the formation of gametes (sperm and egg). Reproduction by meiosis allows for species survival and it increases genetic variability.

The process, during which the germ cells are generated is called meiosis. It represents nature's solution to the problem of chromosome doubling that would occur, if two diploid cells, i.e. two cells with a double set of chromosomes would fuse. Accordingly does meiosis produce haploid germ cells, with maternal and paternal germ cell fusing at fertilization and thus generating a diploid fusion product, the zygote. Meiosis is made up by two subsequent processes, both of which resemble mitosis. In the first process are the homologous chromosomes separated. It has an unusually long prophase that is subdivided into different stages They are followed by metaphase, anaphase and telophase.

Two nuclei fuse upon fertilization, so that the number of chromosomes does necessarily double. If this thought is spun further, would an greater growth of the number of chromosomes from generation to generation have to be expected. This is not


As a result of the meiosis of a diploid cell form four haploid cells, of which one or all can develop into gametes.

During prophase, the replicated chromosomes undergo extensive condensation. The chromosomes are greatly thickened and shortened but are still contained within the nuclear envelope. Late in prophase, within some minutes of the nuclear envelope breakdown, the mitotic spindle begins to grow, and two zones become visible, with one on each side of the nucleus. With continued spindle expansion, the nucleus quickly becomes compressed and appears circular. Prophase ends with the sudden dispersion of the nuclear envelope, and the chromozone mass is no longer occupying a discrete, circular shape zone in the cell.

Mitosis is the process that facilitates the equal partitioning of replicated chromosomes into two identical groups. Before the breakdown can occur, the chromosomes must become aligned so that the separation process can occur in an orderly fashion. The alignment of replicated chromosomes and their separation into two groups. Both the alignment and separation processes are the consequence of the chromosomes interacting with structures, known as microtubules. The microtubules become organized into an array known as a spindle, which forms early in mitosis, and then breaksdown as mitosis nears completion. Mitotic spindles are visible in living cells with the polarizing light microscope. Some of the spindle microtubules become attached to the chromosomes at sites known as kinetochores. They reside near the place on the chromosome known as its centromere, which can be observed with the light microscope. There are two kinetochores on each replicated chromosome (one on each chromatid), and when the replicated chromosome splits apart at its centromere at the onset of anaphase, each daughter chromosome possesses one centromere and one kinetochore. The linkages between kinetochores and microtubules are thought to be central in controlling both the positioning of the replicated chromosome at the central portion of the spindle during the alignment phase, and in moving the daughter chromosomes apart after they split at their centromeres. The separation of daughter cells from each other is a process known as cytokinesis, and is separate from mitosis. In cytokinesis, animal and pl

Some common words found in the essay are:
, Cell Division, Meiosis Meitosis, homologous chromosomes, replicated chromosome, replicated chromosomes, nuclear envelope, spindle pole regions, germ cells, daughter chromosomes, chromosomes separated, anaphase telophase, pole regions, germ cell, Bibliography None, metaphase anaphase telophase, processes resemble mitosis, chromosomes haploid set, homologous chromosomes separated,
Approximate Word count = 1552
Approximate Pages = 6 (250 words per page double spaced)


  

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