Mitosis and meiosis go through the same phases of interphase, prophase, metaphase, anaphase, telophase, and cytokinesis. Interphase occurs when chromatins duplicate in the nucleus. It then moves into prophase where the chromatins fold into chromosomes, the nuclear membrane dissolves, and spindle fibers form. I will mention later a difference that occurs in prophase I of meiosis but not during the prophase phase of mitosis. During metaphase, the chromosomes are pulled to the center of the cell by the spindle fibers, while in mitosis the tetrads are pulled to the center of the cell. During the anaphase of mitosis, chromosomes divide into chromatids and are pulled to opposite sides of the cell. During meiosis, the tetrads are separated back into the chromosomes and pulled to opposite sides of the cell. Then during telophase the nuclear membrane develops again around the genetic material. Towards the end of the anaphase phase, cytokinesis, the division of the cytoplasm, begins. The cell begins to divide at the end of anaphase and continues after the end of telophase. Say no to plagiarism. Get a tailor-made essay on "Why Violent Video Games Shouldn't Be Banned"? Get an original essay The interesting thing is that meiosis goes through the same steps, but twice. There are also some variations between the two processes and the steps required to complete cell divisions. The first thing to note about the differences between these two processes is that mitosis is the division of normal body cells and meiosis is the division of a sperm or egg cell. The next difference is that mitosis is the division of a diploid mother cell with forty-six chromosomes into two diploid daughter cells, both with forty-six chromosomes identical to the mother. Meiosis takes a diploid parent cell with forty physical chromosomes and divides it into four haploid cells with twenty-three chromosomes each. Meiosis does this by going through all these phases twice actually. Another difference occurs during prophase. During mitosis, the chromosomes align themselves, in single file in the center of the cell. During meiosis, chromosomes align two by two into what are called tetrads through a process called synapsis, which I'll return to in a moment. Further down the road, in anaphase, another variation occurs between these two. During mitosis, chromosomes divide into so-called chromatids. During anaphase in meiosis the tetrads divide again into the chromosomes. As I said before, synapsis is the process during meiosis where chromosomes join together to form tetrads. The synapse is important because it allows for another process called crossover. Crossovers occur within each tetrad when the free end of a maternal and paternal chromatid (as they are colloquially called) wrap around each other at one or more points. This allows the exchange of genetic material between the two chromatids. This occurs only in prophase I, not in prophase II, in any other stage either meiosis or mitosis. STDs, or STIs, are one of the biggest problems we face as a nation today, for the simple fact that everyone loves sex. The most common bacterial sexually transmitted disease is called chlamydia. It affects the cervix in women and both the urethra and rectum in men. It may even show no symptoms, which is problematic because untreated chlamydia can cause serious problems later in life. Some symptoms that appear in women are pain during sexual intercourse and subsequent bleeding, lower abdominal pain, irregular menstrual bleeding, more frequent need to urinate, pain during urination and increased..
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