1. Reproduction and Development
Chapter 38
The last unit! 

2. Human Reproductive Systems
Male Anatomy

3. Testes Produce sperm and hormones
Seminiferous tubules  small, coiled tubes
Meiosis  1 cell = 4 functional sperm

5. Epididymis Matures and stores sperm Located anterior to each testis
300 million mature sperm per day

6. Scrotum Outpocketing of body wall Contains testes and epididymises
Temperature 3o C cooler than body temp.

7. Vas deferens
Tubes connecting epididymises to the urethra

8. Urethra
Tube exiting body
Transport of urine and semen

9. Seminal vesicles Secrete a fluid high in fructose
Energy for mobile sperm

10. Prostate gland Secretes a thinner fluid for mobility
Closes off urinary bladder during ejaculation

11. Bulbourethral glands Cowper’s gland Secrete a clear alkaline fluid
Protection of sperm against acidic female reproductive tract

12. Semen
Mixture of sperm and secretions

13. Penis
Specialized adaptation for sperm delivery

14. Puberty in males

15. Hypothalamus Controls pituitary secretions FSH  sperm production
LH  testosterone production

16. Secondary sex characteristics
Growth and maintenance of gonads
Production of sperm
Increased body hair growth
Increased muscle mass
Increased growth of long bones
Deepening of voice

17. Human Female Anatomy

18. Ovaries Produce egg cells in follicles Production of hormones
Meiosis  1 cell = 1 functional egg
3 polar bodies that form the yolk

19. Oviducts Fallopian tubes Transport of egg to uterus
Fertilization occurs here

21. Uterus Pear-shaped organ of smooth muscle
Embryonic development occurs here

22. Cervix
Narrow lower end of uterus

23. Vagina
Birth canal
Muscular passageway exiting body

24. Puberty in females

25. Hypothalamus Controls pituitary FSH  development of mature follicle
Secretion of estrogen by ovary
LH  stimulates ovulation

26. Secondary sex characteristics
Growth and maintenance of gonads
Increased body hair growth
Increased growth of long bones
Broadening of hips
Fat deposits: breasts, buttocks, thighs
Onset of menses

27. Egg cell production Egg cells start development before birth
Arrested in prophase I
Primary oocytes  2 million
40,000 left at puberty
FSH stimulates meiosis
Ovulation  mature egg ruptures through ovary
400 eggs over lifetime

28. Menstrual cycle
Producing mature eggs and preparing uterus for implantation

29. Flow phase Days 1-5 Shedding of endometrial lining
Uterus contracts to expel
Blood levels of FSH begin to rise

30. Follicular phase Days 6-14 (variable) Follicle develops
Estrogen  repair of uterine lining
LH blood level spikes just before ovulation
Ovulation  Day 14
Increased body temp., cervix produced mucous

31. Luteal phase Days 15-28 LH  follicle fills with cells (corpus luteum)
Corpus luteum secretes progesterone  thickens uterine lining
Progesterone inhibits FSH and LH
Uterine lining begins to shed

33. Development before birth

34. Fertilization and implantation
Egg cell  24 hours
Sperm cells  48 hours

35. Fertilization n + n = 2n (zygote)
Cap of sperm  enzymes to penetrate egg
Sperm nucleus enters egg
Egg membrane changes  only 1 sperm
2 nuclei fuse  zygote

38. Zygote travels to uterus
6 days
Cleavage  repeated mitotic divisions
Blastocyst  hollow ball of cells

41. Implantation
Embryo implants in thick uterine lining
7-8 days

43. Embryonic membranes and the placenta

44. Amnion Thin inner membrane filled with amniotic fluid Shock absorber
Regulates embryonic body temperature

45. Allantois Outgrowth of digestive tract
Umbilical cord forms from blood vessels

46. Chorion
Outer membrane
Chorionic villi become part of placenta

47. Placenta From chorion and uterine wall
Exchange of nutrients and wastes
Blood vessels from mother and embryo have no direct contact  diffusion

49. Hormonal maintenance of pregnancy
hCG (human chorionic gonadotropin) secreted by embryo
Keeps corpus luteum from degenerating
Steady supply of progesterone
After 3 months, uterus takes over

50. Multiple embryos Fraternal twins  2 eggs, 2 sperm
Identical twins  1 egg, 1 sperm
1 zygote separates into 2 separate embryos

51. Fetal development
Growth, development, and cellular differentiation

52. First trimester Organ systems form
Sensitive to outside influences  alcohol, tobacco, other drugs, malnutrition
8th week  all are formed (fetus)
Sex can be determined

53. Second trimester Growth Could survive outside uterus with assistance
Cannot maintain constant body temp.
Immature lungs  no regular respiratory rate

55. Third trimester Rapid growth Mass of fetus more than triples
7th month  fetus moves
8th month  eyes open
9th month  head in downward position

56. Gestation
Length of pregnancy
About 266 days

57. Birth, growth, and aging

58. Birth

59. Labor Oxytocin secreted from pituitary
Cervix dilates, uterus contracts
Up to or over 24 hours

60. Expulsion Uterine contractions force baby through birth canal
20 minutes to 1 hour

61. Placental stage Expelled 10-15 minutes after birth
Uterus contracts  prevents hemorrhaging

62. Growth
hGH

63. Infancy First 2 years Physical coordination Mental development
Tremendous growth
Learn to control limbs, walk, first words

64. Childhood Infancy to adolescence Steady growth
Learn to reason and think critically

65. Adolescence
Begins at puberty
Reach maximum physical stature and mass

66. Adulthood
No more growth

67. Aging Decreased metabolism and digestion
Skin loses elasticity  wrinkles
Less pigment in hair follicles
Bones  thinner and more brittle
Vision and hearing might diminish

68. Aging cont.
Stature may shorten  disks between vertebrae become compressed
Genetic causes
Rate varies  interaction of genes and environment