1. 1 Ovaries Ovaries Blood supply Blood supply ovarian follicles ovarian follicles Cells around the oocyte are called: Cells around the oocyte are called: Follicle cells Follicle cells Granulosa cells Granulosa cells

2. 2 Follicles Follicles Primordial follicle Primordial follicle Primary follicle Primary follicle Secondary follicle Secondary follicle Graafian follicle Graafian follicle Ovulation Ovulation Corpus luteum Corpus luteum Oogenesis: Puberty -At puberty, one activated primary oocyte produces two haploid cells -Ovulation -If penetrated by sperm the second oocyte completes meiosis II

3. 3 Ovarian Cycle  ovaries grow and secrete small amounts of estrogens that inhibit the hypothalamic release of GnRH  As puberty nears, GnRH is released Monthly Follicular phase Follicular phase Ovulation Ovulation Luteal phase Luteal phase

4. 4

5. Fertilization and Embryonic Development Fertilization = The fusion of two haploid gametes (egg and sperm) n – haploid, 23 chromosomes 2n – diploid, 46 chromosomes 5

6. The three stages of Fertilization 1. Penetration 2. Activation 3. Fusion 6

7. Early Development 7 Cleavage Implantation Gastrulation

8. Gastrulation Ectoderm Ectoderm Endoderm Endoderm Mesoderm Mesoderm 8

9. Extra Embryonic Membranes: 1. Yolk Sac 2. Amnion 3. Allantois 4. Chorion 9