CELL DIVISION
MEIOSIS AND GENETIC VARIATION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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prophase I-the major event is crossing-over.
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anaphase I-this is where the homologous chromosomes are separated.
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interphase-this occurs only one in both meiosis and mitosis
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metaphase I-This is where homologous chromosomes line up in pairs in the middle of the cell.
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Detailed explanation-1: -There are two major events that occur in both mitosis and meiosis i.e. the division of nuclear material called karyokinesis and the division of cytoplasm called cytokinesis. Karyokinesis means the process of division of the nucleus during mitosis or meiosis.
Detailed explanation-2: -The S phase of a cell cycle occurs during interphase, before mitosis or meiosis, and is responsible for the synthesis or replication of DNA. In this way, the genetic material of a cell is doubled before it enters mitosis or meiosis, allowing there to be enough DNA to be split into daughter cells.
Detailed explanation-3: -Interphase doesn’t occur a second time because after the first division of meiosis the cell only contains half the chromosomes necessary to perform its functions.
Detailed explanation-4: -Like mitosis, meiosis also has distinct stages called prophase, metaphase, anaphase, and telophase. A key difference, however, is that during meiosis, each of these phases occurs twice-once during the first round of division, called meiosis I, and again during the second round of division, called meiosis II.