Meiosis
??? ??? ??? ??? ??? ?? ? Meiosis??I. Formation of Haploid Cells???? A. In animals, meiosis produces gametes, haploid reproductive cells???? ??? 1. In humans, sperm + egg cells???? ??? 2. Each contain 23 (1n) chromosomes???? ??? 3. Fusion results in a zygote that contains 46 (2n) chromosomes???? B. Undergo the G1, S, and G2 phases of interphase.???? C. Begin meiosis with a duplicate set of chromosomes, but undergo meiosis twice???? ??? 1. Diploid (2n) cells result in four haploid (1n) cells???? D. Meiosis I- Stages of the first cell division???? E. Meiosis II- Stages of the second cell division?II. Meiosis I???? A. Prophase I???? ??? 1. DNA coils into chromosomes, spindle fibers appear (like mitosis)???? ??? 2. Nucleolus & nuclear membrane disassemble (like mitosis)???? ??? 3.