1. The Reproductive System

2. Reproduction Primary function: to produce offspring
genetic material passed from generation to generation
Sharing intimate feelings with another person

3. Some terms to know
Gonads: the organs in the body that produce the sex cells (GAMETES)
Male = testes --> Sperm
Female = ovaries --> Ova or Egg cells
Ducts: transport and secrete
Glands: secrete

4. Testes Paired organs located inside the scrotum
Located outside the body to ensure proper temp for sperm production

5. Function of the testes Produce and mature sperm
maturation of sperm takes approximately 74 days
Protect sperm and sperm development--Sertoli cells
Produce testosterone: Leydig cells

6. Functions of Testosterone
the principle male hormone
produced by Cells of Leydig
responsible for the male secondary sexual characteristics:
growth and development
maintenance of sex organs
bone growth
influences sexual behavior
influences final maturation of sperm cells

7. Seminiferous Tubules tightly coiled tubules in testes
Spermatogenesis occurs
Spermatogonia = immature Sperm Cell
Spermatozoa = mature Sperm Cell
Interstitial Cells (Cells of Leydig) = endocrine cells produce and secrete testosterone

8. Epididymis 7 m long Head - superior, receives spermatozoa Body
Tail - leads to ductus deferens

9. Epididymis Functions: 1) Monitors and adjusts tubular fluid
2) Recycles damaged spermatozoa
3) Stores sperm and facilitates maturation

10. Ductus (Vas) Deferens
long duct (18 inches) passageway for sperm from epididymis to urethra
enters the body through the pelvic floor called the Inguinal Canal

11. Ejaculatory Ducts
union of seminal vesicles and the ductus (vas)deferens
eject sperm into the prostatic urethra prior to ejaculation

12. Urethra passageway for sperm and urine to the external environment
measures about 8 inches in length
4 sections of the Urethra

13. Urethra 1. prostatic urethra 2. Membranous urethra 1 3. spongy urethra

14. Urethra 4
4. external urethral orifice

15. Accessory Male Sex Glands
secrete most of the liquid portion of Semen
provides a liquid, nutrious medium for the support of sperm cells

16. Seminal Vesicles Paired, on posterior wall of urinary bladder
Tubular (~ 15 cm)
Produce 60% of semen, hormones, fructose, etc.
Activate sperm (leading to motility)

17. Prostate Gland
about the size of a chestnut located inferior to the urinary bladder - surrounds the urethra
secretes a fluid rich in citric acid, prostatic acid, phosphatase, and prostaglandins
makes up about 13% - of the semen
often site of cancerous growth in males

18. Bulbourethral Glands (Cowper’s Glands)
Pea size, paired, at base of penis
Produce about 10% of semen
Alkaline mucus - neutralize acidic nature of female vagina

19. Semen (Seminal Fluid)
mixture of sperm and secretions of accessory glands
ml of semen per ejaculation (1/2 tsp)
million sperm per ejaculation
if less than 100 million sperm-- male is considered infertile

20. MALE: EXTERNAL GENITALIA

21. SCROTUM supports and protects testes
continuation of abdominal wall skin
Separated by a structure called the raphe

22. SCROTUM Dartos muscle in dermis
Cremaster muscle
Dartos muscle in dermis
Cremaster muscle - continuous with abdominal wall muscles
Involuntary contraction in response to TEMP changes
Temp must be 2-3o Lower than body temp

23. Penis
used to introduce sperm into the female vagina during intercourse
Voids urine (urination)
cylindrical in shape

24. Three parts of penis Body : 3 cylindrical masses of tissue
Corpora Cavernosa Penis ( 2)
Corpus Spongiosum Penis
Made of erectile tissue filled with blood sinuses

25. Penis (cont) Root--portion attached to pubic area
Bulb--attached to abdominal wall
Crus--Attached to muscles that aid in erection

26. Glans penis Slightly enlarged portion of the corpus spongiosum
Separated from body by corona
Contains many nerve endings
Uncircumcised glans contains prepuce or foreskin

27. Penis erection
With sexual stimulation, arteries dilate, veins constrict, large quantities of blood enter sinuses and an erection occurs
Erections occur also to maintain health of penis

28. End of male REPRODUCTIVE System
QUESTIONS?

29. FEMALE REPRODUCTIVE SYSTEM

30. Ovaries the female gonads oogenesis occurs
females are born with all egg cells as they will ever have (500,000)

31. Oogenesis Maturing of an oocyte (egg)
Begins with primary follicles, ends with secondary ooctye
other primary follicles donate material to developing egg

32. Ovarian follicles
each month about 20 primary oocytes are stimulated to undergo meiosis
usually only one of these 20 completes the process of oogenesis & develops into a secondary oocyte

33. Graffian Follicle
Oocyte continues to mature before released by ovary during ovulation
Contains two parts
Antrum and oocyte
Secretes estrogen

34. Ovulation Process where secondary oocyte is released from ovary
About day 14 of cycle

35. Corpus Luteum and Corpus Albicans
Glandular body that develops after release of egg
Secretes progesterone, estrogen, relaxin, inhibin
Becomes corpus albicans if egg is NOT fertilized
Stays in tact during pregnancy

36. Uterine (Fallopian) Tubes
ducts transport ova from site of ovulation to uterus
Infundibulum = funnel shaped, open distal end
Fimbriae = “little fingers” on distal end

37. Uterine (Fallopian) Tubes
Ampulla = widest, longest portion of the uterine tubes
fertilization usually occurs in this region
Isthmus = narrow, constricted, proximal end where the tubes attach to the uterus

38. Uterus
serves as the site of menstruation, implantation of a fertilized ovum, and development and maintenance of fetus during pregnancy
inverted pear shaped muscular organ
has 3 sections or areas
Fundus
Body
Cervix

39. Tissue Layers of the Uterus
Perimetrium = outermost layer
Myometrium = middle, muscular layer
majority of the uterus
consists of three layers of smooth muscle
Endometrium = innermost layer of the uterus
Made of stratum functionalis and stratum basalis

40. Vagina tubular fibromuscular organ lined with mucous membrane
passageway for sperm & menstrual flow
receptacle for penis during sexual intercourse
lower portion of birth canal

41. FEMALE: EXTERNAL GENITALIA

42. Female External Genitalia
Vulva = term used to describe female external genitalia
Mons Pubis = adipose tissue above the pubic symphysis, covered by skin and coarse pubic hair
Labia Majora = an area of longitudinal folds of tissue
Labia Minora = medial longitudinal folds of tissue

43. Female External Genitalia (cont)
Vestibule: the space between the Labia Minora
Bulb of vestibule contain:
Greater Vestibular Glands (Bartholin’s)
produce mucoid substance
Provide lubrication for sexual intercourse

44. Female External Genitalia (cont)
Clitoris: small cylyndrical mass of nervous and erectile tissue
Prepuce: layer of skin from labia minora covers clitoris
Hymen: thin membrane partially covering the vagina
Female External Genitalia (cont)

45. Mammary Glands (Breasts)
modified sudoriferous glands (Sweat Glands)
each gland contains lobes or compartments separated by adipose tissue
amount of adipose tissue between lobes determines breast size
breast size is not related to milk production

46. Mammary Glands (Breasts)
each lobe has compartments called lobules
Inside lobules are milk secreting cells
Nipple = the raised area on the breast that an infant suckles to receive milk and stimulate lactation
Areola = the dark, circular, pigmented area that encircles the nipple

47. the process of milk production, secretion, and ejection
Lactation
the process of milk production, secretion, and ejection

48. Menstrual and Ovarian Cycles
Ovarian Cycle = maturation and ovulation of an ovum
Menstrual Cycle = changes of the endometrial lining of the uterus
preparation for implantation of a fertilized ovum
correlated with each other and are under the influence of hormones

50. Endocrine influence Hypothalamus stimulates pituitary FSH and LH
FSH : ovarian follicles
LH: ovulation--stimulates production of estrogen, progesterone and relaxin
Ovaries produce estrogen and progesterone

51. Estrogen 6 different types
development and maintenance of the female reproductive system
helps control fluid and electrolyte balance
Keeps heart strong
Keeps bones strong

52. Progesterone
hormone of maturation
prepares the endometrial lining for implantation
stimulates milk production and secretion
Drop in progesterone starts menstrual cycle

53. Relaxin and Inhibin
Relaxin = produced by the corpus luteum during pregnancy
Relaxin = most prominent during the final trimester of pregnancy
relaxes the pubic symphysis and helps dilate the cervix
Inhibin = is the negative feedback hormone for estrogen and progesterone

54. DEVELOPMENT and INHERITANCE

55. HUMAN DEVLOPMENT The continuous process of body changes
Begins at fertilization
Continues until death
Two periods
Prenatal: Conception until birth
Postnatal: birth until death

56. Spermatogenesis vs. Oogenesis
Spermatogenesis: production & maturation of sperm
Oogenesis: production & maturation of egg

57. Prenatal Development changes that occur prior to Birth
Divided into Two Periods
The Embryonic Period
fertilization until eight weeks
The Fetal Period
eight weeks until birth

59. Fertilization also called “Conception” union of sperm & oocyte
one sperm cell penetrates layers of the egg
aided by enzyme on head of sperm
oocyte cell membrane changes biochemically

60. The Embryonic Period first 8 weeks of life
fertilized egg called Zygote
first cell divisions of Zygote are called:
CLEAVAGE --result in ball of cells called Morula
Morula turns into a large mass of cells called Blastocyst

61. Blastocyst Stages of Development
Implantation = attachment of the Blastocyst to the endometrium
about 6 days after fertilization
Blastocyst differentiates into primary Germ Layers (Endoderm, Mesoderm, Ectoderm)

62. Trophoblast Development and Implantation
Becomes Trophoblast-- layers form (Chorion, Amnion, and Yolk Sac) begin to form around the embryo
Called pregnancy when implanted

63. Embryonic Period 5 weeks after conception
Bones begin to form, major blood vessels form
other systems form
Heart forms & starts to beat
Nervous system forms

64. Embryonic Development
Development of Body Form
weeks three to eight
the embryo resembles a human like figure
Development of Organs
most major organs appear during the first eight weeks of development

65. Embryonic Period 8 weeks
Resembles a human and is called a FETUS—Latin word for OFFSPRING

66. Fetal Development 18 weeks Face looks human Joints form Bones ossify
Rapid development of body organs

67. Fetal Development
Can recognize sounds
Urine forms

68. Fetal Development
18 weeks
Rapid development of body organs

69. Fetal Development 20 weeks
Lanugo appears-protects fetus from waste in amniotic fluid
Fetal movements felt by mother
Hair appears on head

70. Fetal Development
20 weeks

71. Fetal Development 24 weeks
Sense of taste develops, lungs are ready to produce surfactant
Substantial weight gain
Eyelids separate
Eyelashs form
Can survive outside womb (viable)

72. Fetal Development 30 weeks Head and body more proportionate
In male, testes descend
Fetus assumes upside down position
Subcutaneous fat deposited

73. Fetal Development 40 weeks Additional subcutaneous fat accumulates
Lungs secrete oxytocin
Lanugo is shed
Fetus is full term
Is ready at 38 weeks

74. Fetal Development

75. Labor
movement of the fetus through birth canal in response to uterine contractions
Three Stages of Labor
Stage One = dilation & effacement
contractions push fetus against cervix
amniotic sac ruptures
cervix dilates
Once cervix dilates to 10 cm Stage Two begins

76. Fetal Development Stage Two = delivery and birth
Stage Three = expulsion of the placenta

77. Stages of Physical Development
Neonate - “newborn”
Infancy
Toddlerhood
Childhood
Adolescence – puberty
Adulthood
Middle Age
Advanced Age