chromosones

chromosones - Principles of Biology Meiosis and Chromosomes...

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Principles of Biology Meiosis and Chromosomes Mitosis Chromosomes occur in homologous pairs The somatic (body) cells of each species contain a specific number of chromosomes. Human cells = 46 (23 pairs) of homologous chromosomes. Gametes only have one set of chromosomes Cells with two sets of chromosomes are said to be diploid. Gametes, eggs and sperm, are haploid, with a single set of chromosomes. Sexual life cycles involve the alternation of haploid and diploid stages. Meiosis Meiosis reduces the chromosome number from diploid to haploid. Meiosis, like mitosis, is preceded by chromosome duplication. In meiosis, though, the cell divides twice to form four daughter cells. Starts with synapsis, the pairing of homologous chromosomes in tetrads. In crossing over o Homologous chromosomes exchange corresponding segments o Meiosis I separates each homologous pair and produces two daughter cells, each with one complete set of chromosomes. Meiosis II
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chromosones - Principles of Biology Meiosis and Chromosomes...

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