The Reproductive System

1. 32 The Reproductive System

2. Learning Outcomes (cont.) 32.1 Summarize the organs of the male reproductive system including the locations, structures, and functions of each. 32.2 Describe the causes, signs and symptoms, and treatment of various disorders of the male reproductive system. 32.3 Summarize the organs of the female reproductive system including the locations, structures, and functions of each. 32.4 Describe the causes, signs and symptoms, and treatment of various disorders of the female reproductive system.

3. Learning Outcomes (cont.) 32.5 Explain the process of pregnancy, including fertilization, the prenatal period, and fetal circulation. 32.6 Describe the birth process, including the postnatal period. 32.7 Compare several birth control methods and their effectiveness. 32.8 Explain the causes of and treatments for infertility. 32.9 Describe the causes, signs and symptoms, and treatments of the most common sexually transmitted infections.

4. Introduction • Male and female reproductive systems • Function together to produce offspring • Produce important hormones

5. Testes Produce sperm and testosterone Divided into lobules Held in the scrotum Seminiferous tubules In the lobules of the testes Contain spermatogenic cells Interstitial cells produce testosterone Male System The Male Reproductive System

6. Sperm Cell Formation Spermatogenesis Spermatogonium (46 chromosomes) Mitosis Primary spermatocytes (46 chromosomes) Meiosis at puberty Secondary spermatocyte Secondary spermatocyte 2nd meiotic division Spermatid Spermatid Spermatid Spermatid

7. Head Nucleus with 23 chromosomes Covered by an acrosome Midpiece - mitochondria Tail Flagellum Propelsthe sperm Sperm Cell Formation (cont.)

8. Epididymis – where spermatids mature into sperm Vas deferens – carries sperm cells to urethra Seminal vesicles – secrete seminal fluid Sugar Prostaglandins Male System Internal Accessory Organs – Male

9. Prostate gland Alkaline fluid that protects sperm Contractions assist with expulsion of semen Cowper’s glands – fluid to lubricate end of penis Semen Sperm cells Fluids Male System Internal Accessory Organs – Male (cont.)

10. Scrotum Pouch that holds the testes away from the body Lined with serous membrane that secrets fluid Penis Shaft Glans penis Prepuce Functions Deliver sperm Urination Male System External Organs – Male

11. Erection, Orgasm, and Ejaculation • Erection – erectile tissue becomes engorged with blood • Orgasm - emission occurs • Ejaculation – semen is forced out of the urethra

12. Male Reproductive Hormones • Gonadotropin-releasing hormone (GnRH) • Follicle-stimulating hormone (FSH) • Luteinizing hormone (LH) • Testosterone • Secondary sex characteristics • Maturation of male reproductive organs • Regulated by negative feedback

13. Apply Your Knowledge Matching: ___ Vasectomy ___ Mixture of sperm and fluids ___ Sperm cell formation ___ Secrete alkaline fluid/ prostaglandins ___ Produce testosterone ___ GnRH ___ Erectile tissue ANSWER: • Spermatogenesis • Testes • Penis • Vas deferens • Hypothalamus • Semen • Seminal vesicle D F A G B Correct! E C

14. Common Diseases and Disorders of the Male Reproductive System

15. Common Diseases and Disorders of the Male Reproductive System (cont.)

16. Apply Your Knowledge ANSWER: Match: More common in men over 40 years old. Common in older men; symptoms include difficulties with urination. More common in males 15-30 years old; aggressive. Often starts as urinary tract infection; symptoms include swelling of the scrotum and painful ejaculation. • BPH • Epididymitis • Prostrate cancer • Testicular cancer C A D B

17. Female System The Female Reproductive System • Ovaries • Produce ova, estrogen, and progesterone • Medulla ~ nerves and lymphatic and blood vessels • Cortex ~ ovarian follicles

18. Ovaries and Ovum Formation • Primordial follicles • Primary oocyte • Follicular cells Oogenesis At puberty Primary oocyte stimulated to continue meiosis Polar body Secondary oocyte Released during ovulation Ovum, if fertilized

19. Internal Accessory Organs – Female • Fallopian tube – oviduct • Infundibulum and fimbriae • Fringed, expanded end of fallopian tube near ovary • Function to “catch” an ovum • Muscular tube • Lined with mucous membrane and cilia • Propels ovum toward uterus Internal Accessory Organs

20. Uterus Receives embryo and sustains its development Divisions Wall ~ three layers Vagina Extends from uterus to outside body Rugae Wall ~ three layers Internal Accessory Organs – Female(cont.) Internal Accessory Organs

21. Mammary glands Secretion of milk Structures Nipple Areola Alveolar glands External Accessory Organs - Female

22. Female System External Genitalia – Female • Vulva • Labia majora • Adipose tissue and skin • Form the mons pubis • Labia minora • Vascular folds of skin • Form hood over clitoris • Vestibule • Bartholin’s glands • Clitoris • Contains female erectile tissue • Rich in sensory nerves • Perineum – between vagina and anus

23. Erection, Lubrication, and Orgasm • Nervous stimulation • Clitoris becomes erect • Bartholin’s glands activate • Vagina elongates • Orgasm • Sufficient stimulation of clitoris • Walls of uterus and fallopian tubes contract to propel sperm

24. Female Reproductive Hormones Hypothalamus secretes GnRH Anterior pituitary releases FSH & LH GnRH Stimulates Ovaries to produce estrogen and progesterone • Estrogen and progesterone are responsible for development of secondary sex characteristics

25. Reproductive Cycle • Menstrual cycle • Regular changes in uterine lining • Shedding of lining and bleeding • Menarche – first menstrual period • Menopause – termination of cycle due to normal aging of ovaries

26. Lining more vascular and glandular Then releases LH Triggers ovulation Follicular cellsbecomecorpus luteum,which secretesprogesterone Reproductive Cycle (cont.) Anterior pituitaryreleases FSH Uterine lining thickens Ovarian folliclematures and secretesestrogen • Without fertilization • Corpus luteum degenerates • Estrogen and progesterone levels fall • Uterine lining breaks down– menses starts • Cycle begins again with release of FSH

27. Apply Your Knowledge YIPPEE! True or False: ___ The ovaries only produce estrogen. ___ Ovulation is the process of ovum formation. ___ The fallopian tube is also called the oviduct. ___ The endometrium is the outer layer of the uterine wall. ___ Alveolar glands produce milk. ___Oxytocin induces the alveolar glands to deliver milk through the nipples. ___ Menarche is the termination of the menstrual cycle. ___ Menopause occurs due to normal aging of the ovaries. ANSWER: produce estrogen and progesterone F F Oogenesis T F innerlayer T F lactiferous ducts F first T

28. Common Diseases and Disorders of the Female Reproductive System (cont.)

29. Common Diseases and Disorders of the Female Reproductive System

30. Diseases and Disorders of the Female Reproductive System (cont.)

31. Apply Your Knowledge Matching: ___ Inflammation of the cervix A. Dysmenorrhea ___ Cancer common in post-menopausal women B. Cervical cancer ___ Develops slowly; detected by Pap smear C. Fibroids ___ Uterine tissue grows outside uterus D. Breast cancer ___ Second leading cause of cancer death in women E. Cervicitis ___ Severe menstrual cramps F. Endometriosis ___ Benign tumors in the uterine wall G. Uterine cancer ANSWER: G o o d J o b ! E G B F D A C

32. Pregnancy • Condition of having a developing offspring in the uterus • Fertilization • Sperm penetrates cell membrane • Zona pellucida becomes impenetrable • Zygote • Union of ovum and sperm nuclei • 46 chromosomes

33. The Prenatal Period • Zygote – undergoes rapid mitosis • Morula – ball of cells • Blastocyst • Implants in the endometrial wall • Inner cell mass becomes the embryo • Others plus cells from uterus form the placenta

34. Formation of Placenta Amnion Umbilical cord Yolk sack Internal organs and external structures Embryonic period Inner cell mass organizes into the primary germ layer Ectoderm Mesoderm Endoderm The Prenatal Period (cont.)

35. Fetal period – fetus Rapid growth 5th month Skeletal muscles active Growth rate slows 6th month – gains weight Last 3 months – fetal brain cells rapidly divide GI and respiratory systems last to develop The Prenatal Period (cont.)

36. Fetal Circulation • Placenta and umbilical blood vessels – exchange nutrients, oxygen, and waste products • Unique differences • Foramen ovale ~ bypass lungs • Ductus arteriosus ~ between pulmonary trunk and aorta • Ductus venosus ~ bypasses liver

37. Hormonal Changes During Pregnancy • Human chorionic gonadotropin (HCG) • Secreted by embryonic cells • Maintains the corpus luteum • Estrogen and progesterone • Secreted by corpus luteum and placenta • Stimulate uterine lining to thicken • Inhibit release of FSH and LH from anterior pituitary gland

38. Relaxin Inhibits uterine contractions Relaxes ligaments of pelvis Lactogen – stimulates enlargements of mammary glands Aldosterone –increases sodium and water retention Parathyroid hormone (PTH) – blood calcium levels Hormonal Changes During Pregnancy (cont.)

39. Apply Your Knowledge What are the primary germ layers and what tissue develops from them? • ANSWER: The primary germ layers are the: • Ectoderm – nervous tissue and some epithelial tissue • Mesoderm – connective tissue and some epithelial tissue • Endoderm – epithelial tissue only Right!

40. The Birth Process • Begins when progesterone levels fall • Prostaglandins stimulate uterine contractions • Uterine contractions stimulate release of oxytocin • Oxytocin stimulates strong uterine contractions

41. The Birth Process (cont.) • Dilation • Effacement • Lasts 8 – 24 hours • Expulsion or parturition • Actual birth stage • May take 30 minutes or less • Placental stage • Blood vessels constrict • Placenta separates from uterine wall and is expelled

42. Six-week period Neonatal period – first four weeks Neonate adjusts to life outside uterus Milk production and secretion Prolactin Oxytocin Production continues as long as breast-feeding continues The Postnatal Period

43. Apply Your Knowledge What are the three stages of the birth process and what occurs during each? • ANSWER: The three stages are: • Dilation – the cervix thins, softens (effacement), and dilates to approximately 10 cm • Expulsion – also called parturition; the actual birth stage • Placental stage – placenta separates from uterine wall and is expelled Impressive!

44. Contraception

45. Contraception (cont.)

46. Contraception (cont.)

47. Apply Your Knowledge Your patient has just been told that she is pregnant, but she does not understand why she could get pregnant. She states, “ I have been very careful in using the rhythm method of birth control.” What patient teaching would you do to assist her to understand? ANSWER: The rhythm method is not as effective as other birth control, because it is sometimes difficult to tell when ovulation occurs. Good Answer!

48. Infertility • Inability to conceive • Primary • Secondary • Causes • 15% unknown • 35% male-related problems • 50% female-related problems

49. Some male-related factors Impotence Retrograde ejaculation Low or absent sperm count Decreased testosterone Some female-related factors Pelvic inflammatory disease No ovulation or menstrual cycle Endometriosis Older than 40 years Infertility (cont.)

50. Infertility (cont.) • Tests • Semen analysis • Monitoring of morning body temperature • Blood hormone measurements • Endometrial biopsy • Urine analysis for LH • Hysterosalpingogram • Laparoscopy