Lecture outline

1. Lecture outline • Puberty & Development of Secondary Sexual Characteristics • Establishing the ovarian cycle • Breast development • Pubic and Axillary Hair growth • Human Reproductive Anatomy • Pelvic Girdle • External Genitalia • Uterus, Ovaries & Oviducts • Breasts • Gender Differences: an anatomical perspective • Male Reproductive Tract

2. Puberty & Development of Secondary Sexual Characteristics • Puberty • Hormones involved in regulating changes involved with puberty

3. Endocrine organs involved in sex development:

5. Hypothalamus & Pituitary: • Hypothalamus secretes GnRH (gonadotropin releasing hormone), which in turn regulates the Pituitary gland. • GnRH is secreted through a complex of veins routed directly to the • Once at anterior portion of pituitary, GnRH • FSH (Follicle stimulating hormone) • Estrogen acts as positive feedback to regulate hypothalamus to stimulate production of GnRH, which triggers increased LH • LH (Leutenizing hormone)

6. Ovaries & estrogen secretion • 3 major estrogens secreted • Estradiol • Estrone • Estriol

7. Estradiol • Breast development and maintenance • Adding fat to breasts, hips, thighs during puberty • Improving bone strength and density • Accelerating bone maturation and bringing epiphyses to closure, completing growth • Growth of the uterus • Development of the endometrial lining to a thickness necessary to support pregnancy and menstruation • Thinning of cervical mucus at ovulation • Promoting and maintaining vaginal mucosal thickness and secretions • Serving as the primary feedback to the brain of sex hormone levels in both males and females. • Participating in triggering ovulation • Preservation of egg cells • Enabling spermatogenesis • Effect on lipids • Vascular effects • Cerebral effects

8. A. Establishing the ovarian cycle- Gonadotropins trigger changes: • From birth to puberty, the gonads secrete • Estrogens inhibit the • As the brain matures, the hypothalamus begins to override the negative feedback and begins GnRH secretion • GnRH stimulates the anterior pituitary to release FSH & LH • Adult cyclic pattern achieved & hormonal interactions stabilize – events heralded by

10. B. Breast development • Mammary glands = • Thelarche (breast development) occurs as a result of the increased estrogen levels

11. Tanner’s 5 stages of breast development (based on Caucasian girls)

12. C. Pubic and Axillary Hair growth • Andrenarche = • Pubarche = • In most girls, pubic hair first appears along the edges of the labia majora, and spreads forward over the next 2 years. • By 3 years into puberty, the pubic triangle is densely filled. • Within another 2 years pubic hair also grows from the near thighs in most young women, and sometimes a small amount up the line of the abdomen toward the umbilicus.

13. II. Adult Female Anatomy • External Genitalia • Uterus, Ovaries & Oviducts • Breasts

14. A. External Genitalia

17. Shaft contains 2 corpora cavernosa consisting of erectile tissue.

19. B. Uterus, Ovaries & Oviducts • Uterus: • Cervix: • External Os – • Internal Os – • Endocervical canal – • Endocervical glands

20. The cervix convulses during orgasm and the external os dilates in order to facilitate the transfer of semen from vagina into the uterus.

22. Positions of uterus • The uterus is very mobile and its position between the rectum and bladder varies depending on posture, how full the bladder or rectum is, and # of children borne

23. 2) Ovaries & Oviducts

24. C. Breasts

25. A fat-tailed dunnart with young attached to her teats

26. III. Gender Differences: an anatomical perspective

27. A. Male Reproductive Tract

28. B. Skeletal differences Os coxae

29. 1. Female v. Male Pelvis • Anthropiod & android pelvis more common in males

30. Position of reproductive organs within the pelvic girdle

31. 2. Angle of pelvic tilt

32. 3. Q-angle differences