1. The Reproductive System
Gonads—
Duct system—
External genitalia—

2. The Reproductive System
Gonads—Testes / Ovaries—produce:
gametes (sex cells) and
hormones
Duct system —delivers gametes
External genitalia —for intercourse

3. Male Reproductive System Overview
Testes
Duct system —Epididymis / Ductus (vas) deferens / Urethra
(Accessory organs --Seminal vesicles / Prostate / Bulbourethral glands)
External genitalia —Penis / Scrotum

4. Male Reproductive System
Figure 16.2a

5. Male Reproductive System
Figure 16.2b

6. Testes
Figure 16.1

7. External Genitalia
Three areas of spongy erectile tissue around urethra
Erections occur when erectile tissue fills with blood during sexual excitement
Nitrogen monoxide (NO) relaxes arterioles
More blood enters penis
Veins constrict—less blood leaves

8. Spermatogenesis
Figure 16.3 (1 of 2)

9. Spermatogenesis
Figure 16.3 (2 of 2)

10. Structure of a Sperm
Figure 16.5b

11. Structure of a Sperm
Figure 16.5a

12. Female Reproductive System
Ovaries
Duct System—Uterine tubes (fallopian tubes) / Uterus / Vagina
External genitalia —Labia, clitoris

13. Female Reproductive System
Figure 16.8a

14. Female Reproductive System
Figure 16.8b

15. External Genitalia (Vulva)
Figure 16.9

16. Ovaries
Figure 16.7

17. Preparing oocytes 0) .

18. Preparing oocytes 0) (Before ova begin to mature) . Primary follicle
Graafian (vesicular) follicle
Ovulation
Ruptured follicle
(The end)

19. Preparing oocytes
0) Total supply of ova present at birth. Releasing ova begins at puberty
Primary follicle —contains immature oocyte
Graafian (vesicular) follicle —growing follicle with maturing oocyte
Ovulation —when the egg is mature, follicle ruptures; occurs every ~28 days
Ruptured follicle  corpus luteum
Reproductive ability ends at menopause

20. Walls of the Uterus Endometrium— Myometrium—
Perimetrium (visceral peritoneum)—

21. Walls of the Uterus Endometrium Inner layer
Allows implantation of fertilized egg
Sloughs off if no pregnancy occurs (menses)
Myometrium —middle layer—smooth muscle
Perimetrium (visceral peritoneum)—outermost serous layer of the uterus

22. Meiosis ♂ ♀
Gamete number ♂ ♀
Gamete size
♂ ♀
Gamete structure

23. ♂ four functional sperm ♀one functional ovum and three polar bodies
Meiosis ♂ ♀
Gamete number
♂ four functional sperm
♀one functional ovum and three polar bodies
Gamete size
♂ tiny ♀ large
Gamete structure
♂ motile, nutrients in seminal fluid
♀ non-motile. nutrient reserves in cytoplasm

24. Follicle Development in Ovary
Oogenesis
Meiotic Events
Follicle Development in Ovary
Before birth
Primary oocyte
Primary follicle
Oocyte
Oogonium (stem cell)
Mitosis
Follicle cells 2n
Figure 16.10, step 1

25. Follicle Development in Ovary
Oogenesis
Meiotic Events
Follicle Development in Ovary
Before birth
Primary oocyte
Primary follicle
Oocyte
Primary oocyte (arrested in prophase I; present at birth)
Oogonium (stem cell)
Mitosis
Growth
Follicle cells 2n
Figure 16.10, step 2

26. Follicle Development in Ovary
Oogenesis
Meiotic Events
Follicle Development in Ovary
Before birth
Childhood
Primary oocyte
Primary follicle
Oocyte
Primary oocyte (arrested in prophase I; present at birth)
Oogonium (stem cell)
Mitosis
Growth
Follicle cells
(ovary inactive) 2n
Figure 16.10, step 3

27. Follicle Development in Ovary
Oogenesis
Meiotic Events
Follicle Development in Ovary
Before birth
Childhood
Primary oocyte
Primary oocyte (still arrested in prophase I)
Primary follicle
Oocyte
Growing follicle
Primary oocyte (arrested in prophase I; present at birth)
Oogonium (stem cell)
Each month from puberty to menopause
Mitosis
Growth
Follicle cells
(ovary inactive) 2n
Figure 16.10, step 4

28. Oogenesis Primary oocyte (still arrested in prophase I)
Mature vesicular (Graafian) follicle
Primary follicle
Growing follicle
Each month from puberty to menopause 2n
Figure 16.10, step 5

29. Oogenesis Primary oocyte (still arrested in prophase I)
Mature vesicular (Graafian) follicle
Primary follicle
Ovulated secondary oocyte
Growing follicle
Each month from puberty to menopause
Meiosis I (completed by one primary oocyte each month)
First polar body
Ovulation
Secondary oocyte (arrested in metaphase II) 2n n
Figure 16.10, step 6

30. Oogenesis Primary oocyte (still arrested in prophase I)
Mature vesicular (Graafian) follicle
Primary follicle
Ovulated secondary oocyte
Growing follicle
Each month from puberty to menopause
Meiosis I (completed by one primary oocyte each month)
First polar body
Sperm
Ovulation
Secondary oocyte (arrested in metaphase II) 2n n
Figure 16.10, step 7

31. Oogenesis Primary oocyte (still arrested in prophase I)
Mature vesicular (Graafian) follicle
Primary follicle
Ovulated secondary oocyte
Growing follicle
Each month from puberty to menopause
Meiosis I (completed by one primary oocyte each month)
First polar body
Meiosis II of polar body (may or may not occur)
Polar bodies (all polar bodies degenerate)
Ovum
Second polar body
Meiosis II completed (only if sperm penetration occurs)
Sperm
Ovulation
Secondary oocyte (arrested in metaphase II) 2n n
Figure 16.10, step 8

32. Follicle Development in Ovary
Oogenesis
Meiotic Events
Follicle Development in Ovary
Before birth
Childhood
Primary oocyte
Primary oocyte (still arrested in prophase I)
Mature vesicular (Graafian) follicle
Primary follicle
Oocyte
Ovulated secondary oocyte
Growing follicle
Primary oocyte (arrested in prophase I; present at birth)
Oogonium (stem cell)
Each month from puberty to menopause
Meiosis I (completed by one primary oocyte each month)
First polar body
Mitosis
Growth
Meiosis II of polar body (may or may not occur)
Polar bodies (all polar bodies degenerate)
Ovum
Second polar body
Meiosis II completed (only if sperm penetration occurs)
Sperm
Ovulation
Secondary oocyte (arrested in metaphase II)
Follicle cells
(ovary inactive) 2n n
Figure 16.10, step 9

33. Uterine (Menstrual) Cycle
Cyclic changes of the endometrium
Regulated by estrogens (EST) and progesterone (PRO)
FSH and LH regulate the production of estrogens and progesterone
~ 28 days for both cycles
Ovulation ~ midway through cycle, ~day 14
FSH & LH
Anterior pitutitaryOvaries
EST & PRO
Ovaries  Anterior pitutitary

34. Fluctuation of Gonadotropin Levels
Figure 16.12a

35. Fluctuation of Ovarian Hormone Levels
Figure 16.12b

36. Ovarian Cycle
Figure 16.12c

37. Uterine (Menstrual) Cycle
Figure 16.12d

38. Developmental Stages of Ovarian Follicle
Figure 16.7

39. Mechanisms of Fertilization

40. Mechanisms of Fertilization
Sperm reach oocyte, enzymes pierce corona radiata
Acrosomal reaction--enzymes pierce oocyte membrane
Receptors on oocyte pull head of sperm into cell
Ca++ ions harden membrane, blocking other sperm
Meiosis II forms ovum and a polar body
Fertilization: genetic material of gametes combine to form a zygote

41. Cleavage Figure 16.15 Fertilization Secondary oocyte Ovulation Uterus
Endometrium
Uterine tube
Blastocyst cavity
Inner cell mass
Trophoblast
Zygote (fertilized egg)
Early cleavage 4-cell stage
Early blastocyst
Late blastocyst (implanting)
Morula
Ovary
(a)
(b)
(d)
(e)
(c)
Figure 16.15

42. The Blastocyst (Chorionic Vesicle)
Primary germ layers are eventually formed
Ectoderm—outside layer
Mesoderm—middle layer
Endoderm—inside layer
The late blastocyst implants in the wall of the uterus (by day 14)

43. Derivatives of Germ Layers
Ectoderm
Nervous system
Epidermis of the skin
Endoderm
Mucosae
Glands
Mesoderm
Everything else

44. Photographs of a Developing Fetus
Figure 16.18a

45. Possible test questions:
What do gonads produce?
How does gametogenesis differ in males and females?
Describe the locations of ovaries and testes.
How do FSH, LH, EST and PRO levels change over the course of a menstrual cycle?
How and why does the uterine lining change over the course of a menstrual cycle?
How does a follicle change over the course of a menstrual cycle?