1. Comparative Anatomy Dr. Tony Serino Misericordia Univ. Biology Dept.
Reproduction
Comparative Anatomy
Dr. Tony Serino
Misericordia Univ.
Biology Dept.

2. Reproduction Function: Survival of species
Production of sex cells (gametes)
Transport the gametes toward each other
Allow gametes to meet (fertilization)
Promote the generation, maintenance and rearing of progeny

3. External Fertilization

5. Gonads: undergo Meiosis to produce gametes
Meiosis (divided into Meiosis I and II)
Meiosis I
Assorts chromosomes by homologous pairs
Then separates the pairs randomly
Reduces the number of chromosomes by half; Diploid to Haploid (2n  n)
Meiosis II
Separates sister chromatids
Progeny cells now have one DNA per chromosome

6. Male Reproduction Gonads: Testis Gamete: Spermatozoa (sperm)
Duct system: to store and transport sperm from gonad to external environment
Supporting structures:
Allow sperm maturation
Allow survival of sperm in ext. environment
Deposit sperm into female vagina
Sensory functions

7. Male Reproductive Anatomy

8. Human Sperm

9. Spermatogenesis

10. Spermatogenesis in the Testis

11. Sperm Anatomy

13. Sperm on Ovum

14. Testis Anatomy

15. Human Testis Spermatic cord Septum dividing testis into lobules
Seminiferous tubules

16. Sertoli and Leydig cells

17. Seminiferous Tubules

18. Sperm leave tubules by ducts and proceed to epididymis

19. Ductus Deferens: carries sperm from epididymis to ejaculatory duct
Passes through inguinal canal back into peritoneal cavity

20. Accessory Sex Glands
Add seminal fluid to sperm to form semen; seminal fluid accounts for 90-95% of semen volume
Seminal fluid will include water, alkaline buffers, mucous, fructose, prostaglandins and enzymes (clotting and de-clotting, anti-bacterial)
Three glands:
Seminal Vesicle ~60% of semen volume
Prostate Gland ~30% of semen volume
Bulbourethral (Cowper’s) Gland <5%

21. Accessory glands (medial view)

22. Accessory Sex Glands (posterior view)

23. Prostate

24. Male Urethra

25. Scrotum and Spermatic Cord

26. Scrotum and Spermatic cord
Provide physical support to testes
Regulate testicular temperature
Cremaster muscle position can change tesits temp.
Pampiniform plexus acts as heat counter current exchanger with testicular artery

27. Penis: Erectile Tissue
Root of Penis (Bulb)
(Crura)
Corpus Spongiosum

28. Penis Anatomy

29. Penis (X.S.)

30. Male Hormones
ABP

31. Female Reproduction Gonad: Ovary Gametes: Ova Duct System:
Transport ovum from ovary to uterus
Site of fertilization;
Receive and transport sperm to ovum
Capacitate sperm
House and support fetus
Deliver fetus
Supporting Structures
Sensory and protective functions

32. Female Anatomy
(oviduct or Fallopian tube)
Vulva

33. Oogenesis *
* First polar body may not divide to form others.

34. Development of Ovum and Follicle

35. Developing follicles

36. Graffian Follicles

37. Ovulated Ovum
Secondary oocyte
Zona Pellucida
Corona Radiata

38. Ovulation

39. Oviduct (Uterine or Fallopian tube)
Ampulla
Isthmus

40. Oviducts: Anatomy
Functions: transportation of ovum, sperm and zygote -capacitation of sperm -site of fertilization

41. Oviduct: three layers mucosa –composed of ciliated simple columnar epithelium muscularis -smooth muscle layer, undergoes peristaltic and segmentation contractions serosa –same as visceral peritoneum

42. Uterus: houses and supports fetus

43. Uterus Types

44. Uterine Layers
Perimetrium

45. Layers of Endometrium
Functional Zone (stratum functionalis) -contains endometrial glands and spiral arteries -is shed each month
Basilar Zone (stratum basale) -regenerative layer that creates functional zone

47. Female External Genitalia

48. Vaginal lining

49. Female Hormones Hypothalamus secretes GnRH
Anterior Pituitary secretes FSH and LH
Theca cells of ovary secrete estrogens
Granulosa cells secrete inhibin
Luteal cells (modified granulosa cells) secrete progesterone

50. Ovarian and Uterine (Menstrual) Cycles

51. Estrous Cycle
-Estrus is a period of sexual readiness for the female; corresponds and may trigger sexual behavior of males; typically no uterine discharge if pregnancy does not occur, tissue is reabsorbed and reorganized
-different species have different timing patterns and number of estrous cycles per season; heavily influenced by day length, health, and pregnancy
Proestrus –follicle and uterine lining development and growth, not yet sexually receptive, dominated by estrogen secretion
Estrus –sexual receptive (behavioral and anatomically), ovulation occurs
Metestrus –sexual receptiveness fades, uterus lining matures with development of corpus luteum and rising secretion of progesterone
Diestrus – functional corpus luteum with high levels of progesterone Anestrus –cessation of sexual activity and ovulation between seasons

52. Development of Reproductive System
Gonads of embryo are sexually indistinguishable
Two sets of ducts present: Mullerian (female) and Wolfian (male)
Female pattern will develop as default
If XY, then testes develop and secrete testosterone
Testosterone stimulates growth of male pattern and degeneration of female pattern

53. Internal Genital Development
Both Wolfian and Mullerian ducts form
With advent of functional testis and testosterone secretion; Wolfian ducts stimulated to develop; Mullerian ducts inhibited by AMH
Without functioning testes, Wolfian ducts degenerate and Mullerian ducts develop female pattern

54. External Genitalia Development

55. Descent of Testes Begins at 7 months gestational
The testes are attached at their inferior margin to the scrotal swelling by the gubernaculum
Growth of the individual and retraction of the gubernaculum allow the testes to descend into the scrotum
An extension of the parietal peritoneum (Vaginal process) maintains an opening into the scrotum and forms the inguinal canal

56. Reproductive Development
Much of the system’s development occurs after birth –during adolescence
Generation of functional sex cells and secondary characteristics dependent on fully functional gonads in both sexes

57. Menopause Cessation of reproductive function with age
Occurs only in women (men slow down function but do not cease unless pathology occurs)
Women see steep decline in pituitary and ovarian hormone production that eventually stops both ovarian and uterine cycles
Woman said to complete menopause after one year without menses