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Meiosis

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Meiosis

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  1. Meiosis

  2. Mitosis vs Meiosis

  3. Meiosis • occurs in gametes (sex cells) and contains haploid (N) number of chromosomes. • Meiosis is a type of cell division which produces gametes containing half the number of chromosomes as parent body cells.

  4. Figure 11-15 Meiosis Section 11-4 Meiosis I * homologous chromosomes (1 set from mom & 1 set from dad)

  5. Figure 11-17 Meiosis II Section 11-4 Meiosis II Prophase II Metaphase II Anaphase II Telophase II Meiosis I results in two haploid (N) daughter cells, each with half the number of chromosomes as the original. The chromosomes line up in a similar way to the metaphase stage of mitosis. The sister chromatids separate and move toward opposite ends of the cell. Meiosis II results in four haploid (N) daughter cells.

  6. Meiosis II (same as Mitosis) • lacks DNA synthesis • ends with 4 haploid (N) cells • these haploid cells are called gametes (sex cells) • Male gamete is sperm • Female gamete is the egg • Sperm and egg combine to form zygote

  7. - In males, meiosis produces 4 haploid gametes called sperm-In females, meiosis produces 1 egg cell and 3 polar bodies* Gonads are organs that produce gametes Example testes or ovaries* Gametes (sex cells)- reproductive cell having haploid number of chromosomes Example- sperm or eggs Gamete Formation

  8. Oogenesis in the Ovaries

  9. Spermatogenesis in the Testes Spermatid

  10. Comparison of Divisions