1. Pre – AP Biology Process of Meiosis (5.4)

2. Somatic vs. Germ

3. Female XX Karyotype (Remember… “kary” means “nucleus”)

4. Male XY Karyotype

5. Germ cells

6. TWO Divisions of Meiosis

7. Meiosis I -First Division

8. Meiosis II - Second Division

9. Spermatogenesis Spermatogonium Primary spermatocyte (in prophase of meiosis I) Mitotic division, producing large numbers of spermatogonia Meiosis I completed Differentiation and onset of meiosis I Secondary spermatocyte Meiosis II Early spermatids Spermatids (at two stages of differentiation) Differentiation Sperm cells Neck Head Midpiece Tail Plasma membrane Mitochondria AcrosomeNucleus Sertoli cell nucleus Lumen of Seminiferous tubule

10. Oogenesis in the ovaries Primary germ cell in embryo Mitotic division Primary oocyte Ovary Oogonium Differentiation Secondary oocyte Completion of meiosis I and onset of meiosis II Ovulation First polar body Entry of sperm triggers completion of meiosis II Second polar body Ovum

11. Variation is the outcome desired

12. Mitosis vs. Meiosis