1 Eric P. Widmaier Boston University Hershel Raff Medical College of Wisconsin Kevin T. Strang University of Wisconsin - Madison *See PowerPoint Image Slides for all figures and tables pre-inserted into PowerPoint without notes. Chapter 17 Lecture Outline * Reproduction Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

2 Hormone Overview Fig. 17-1

3 General Terminology and Concepts; Sex Determination and Differentiation

4 General Principles of Gametogenesis Fig. 17-2

5 Sex Determination Gender is determined by genetic inheritance of two chromosomes known as the sex chromosomes (X and Y). Males possess one X and one Y. Females possess two X.

6 Differentiation of the Gonads During the seventh week of fetal development the SRY gene located on the Y chromosome is expressed, leading to the development of testes in males.

7 Fig Differentiation of Internal and External Genitalia

8 Fig Differentiation of Internal and External Genitalia

9 Male Reproductive Physiology Fig. 17-5Fig. 17-6

10 Anatomy Fig. 17-7

11 Spermatogenesis Fig. 17-8

12 Spermatogenesis Fig

13 Transport of Sperm Fig. 17-6

14 Erection Fig

15 Ejaculation Ejaculation is a spinal reflex mediated by afferent pathways from penile mechanoreceptors leading to contraction of smooth muscle in the epididymis, vas deferens, ejaculatory ducts, prostate, seminal vesicles, and urethra, causing sperm and glandular secretions to be released from the penis.

16 Control of the Testes Fig

17 Testosterone

18 Puberty Puberty, which is the period during which the reproductive organs mature and reproduction becomes possible, usually occurs between 12 and 16 years of age in the male.

19 Andropause Andropause is the steady decrease in testosterone secretion beginning at about 40 years of age.

20 Female Reproductive Anatomy Fig

21 Ovarian Functions Oogenesis Maturation of the oocyte Ovulation Secretion of the female sex steroid hormones

22 Oogenesis Fig

23 Follicle Growth Fig

24 Formation of the Corpus Luteum Fig

25 Control of Ovarian Function Fig

26 Follicle Development and Estrogen Synthesis During the Early and Middle Follicular Phases Fig

27 LH Surge and Ovulation Fig

28 The Luteal Phase Fig

29 Uterine Changes in the Menstrual Cycle Fig

30 Other Effects of Estrogen and Progesterone

31 Puberty Puberty, which is the period during which the reproductive organs mature and reproduction becomes possible, generally usually occurs between 10 and 12 years of age in the female. However, there have been reports recently that girls as early as 8 years of age are undergoing puberty.

32 Pregnancy Egg Transport Intercourse, Sperm Transport, and Capacitation Fertilization

33 Fertilization Fig

34 Fertilization Fig

35 Migration Fig

36 Early Development, Implantation, and Placentation Fig

37 Blood Supply Fig

38 Development Fig

39 Hormonal and Other Changes During Pregnancy Fig

40 Parturition Fig

41 Parturition Fig

42 Lactation Fig

Lactation Fig

44 Infertility Approximately 12 percent of men and women of reproductive age in the United States are infertile. In many cases, infertility can be successfully treated with drugs, artificial insemination, or corrective surgery. When the cause of infertility cannot be treated, it can sometimes be circumvented in women by the technique of in vitro fertilization. The success rate of this procedure, when one egg is transferred, is only about 15 to 20 percent.

45 Menopause Around the age of 50 menstrual cycles become less regular, and ultimately they cease entirely. Menopause and the irregular function leading to it are caused primarily by ovarian failure. The ovaries lose their ability to respond to the gonadotropins, mainly because most, if not all, ovarian follicles and eggs have disappeared by this time through atresia. The hypothalamus and anterior pituitary continue to function relatively normally as demonstrated by the fact that the gonadotropins are secreted in greater amounts. The main reason for this is that the decreased plasma estrogen and inhibin do not exert as much negative feedback on gonadotropin secretion.