2. Warm-up u Pick up the gametes notes and the reproductive system diagrams u Fill in the reproductive diagrams using the Bio I or AP Bio book

3. Lecture #20 Date ________ u Chapter 46 ~ Animal Reproduction

4. Review - Endocrine u Hormones – regular and tropic u Feedback mechanisms - regulation u Endocrine glands and functions u Regulation of –Blood sugar –Calcium

5. Reproductive Circulatory Digestive Excretory Muscular Skeletal Nervous Integumentary Respiratory Lymphatic/Immune ENDOCRINE

6. Endocrine System u Made up of glands that secrete hormones into the bloodstream to deliver messages throughout the body

7. Hormones u Transported in blood u Can be lipid (steroid) or protein u Minute amounts can have big impact on target cells (secondary messenger system – cAMP or IP3)

9. Hypothalamus u Produce ADH and oxytocin which are stored in the posterior pituitary u Controls the secretions of the pituitary gland

10. Pituitary Gland u Posterior –Stores ADH and Oxytocin u Anterior –Secretes FSH, LH, ACTH, TSH, prolactin and Growth hormone u Regulates many of the other endocrine glands

11. TROPIC HORMONES T3/T4 Calcitonin Testosterone Estrogen Progesterone Short-term Epinephrine Long-term Glucocorticoids

12. Thyroid u Secretes thyroxine u Secretes calcitonin u Controls metabolism throughout the body u Lowers blood Calcium

13. Regulating metabolism u Hypothalamus –TRH = TSH-releasing hormone u Anterior Pituitary –TSH = thyroid stimulating hormone u Thyroid –produces thyroxine hormones –metabolism & development t bone growth t mental development t metabolic use of energy t blood pressure & heart rate t muscle tone t digestion t reproduction tyrosine + iodine thyroxine

14. Goiter Iodine deficiency causes thyroid to enlarge as it tries to produce thyroxine

15. Parathyroid u Secretes parathyroid hormone (PTH) u Regulates (raises) the level of calcium in the blood

17. Adrenal u Secretes epinephrine and norepinephrine u Helps body respond to stress

18. Pancreas u Secretes insulin and glucagon u Regulates the level of glucose in the blood

19. liver pancreas liver Regulation of Blood Sugar blood sugar level (90mg/100ml) insulin body cells take up sugar from blood liver stores glycogen reduces appetite glucagon pancreas liver releases glucose triggers hunger high low Feedback Endocrine System Control islets of Langerhans beta islet cells islets of Langerhans alpha islet cells

20. Ovary u Secretes estrogen and progesterone u Controls the development of female secondary sex characteristics and eggs

21. Testis u Secretes testosterone u Controls the development of sperm and male secondary sex characteristics

23. Objectives u Types and strategies of reproduction u Review of mitosis and meiosis u Male and female reproductive organ systems u Spermatogenesis and Oogenesis u Menstrual and ovarian cycles u Fertilization/Ovulation

24. Overview u Asexual (one parent) u fission (parent separation) u budding (corals) u gemmules (porifera) u fragmentation & regeneration (inverts) u Sexual (fusion of haploid gametes) u gametes (sex cells) u zygote (fertilized egg) u ovum (unfertilized egg) u spermatozoon (male gamete)

25. Reproductive cycles u Parthenogenesis –(Type III organisms) – low survival rate of offspring – no time and energy wasted finding mate –unfertilized egg development; haploid, sterile adults (honeybees) u Hermaphroditism – more options –both male & female reproductive systems; sessile & burrowing organisms (earthworms) u Sequential hermaphroditism – don’t have to venture – reversal of gender during lifetime protogynous (female 1st) protandrous (male 1st)

26. Mechanisms of sexual reproduction u Fertilization (union of sperm and egg) external (water) internal u Pheromones chemical signals that influence the behavior of others (mate attractants)

31. Mammalian reproduction, I u The Human Male u Testes ~ male gonads u Seminiferous tubules ~ sperm formation u Leydig cells ~ hormone production u Scrotum ~ outside body temp. u Epididymis ~ sperm development u Vas deferens ~ sperm propulsion u Seminal vesicles ~ semen u Prostate gland ~ anticoagulant; nutrients u Bulbourethral glands ~ acid neutralizer u Penis/urethra ~ semen delivery

32. Male Reproductive Structures

33. Mammalian reproduction, II u The Human Female u Ovaries ~ female gonads u Follicle ~ egg capsule u Corpus luteum ~ hormone secretion u Oviduct ~ fertilization u Uterus/endometrium ~ womb/lining u Cervix/vagina ~ sperm receptacle

34. Female Reproductive Structures

35. Sperm Acrosome MidpieceTa il

36. Sperm Facts u Smallest cell in body u Testes can produce 1000 sperm/second u Sperm can live 5-7 days after leaving the male u 100 million sperm are released at conception u Speed – 1 to 4 mm/hour

37. Spermatogenesis u Puberty until death! u Seminiferous tubules ~ location u Primordial germ cell (2N)~ differentiate into…. u Spermatogonium (2N) ~ sperm precursor u Repeated mitosis into…. u Primary spermatocyte (2N) u 1st meiotic division u Secondary spermatocyte (1N) u 2nd meiotic division u Spermatids (1N)~ Sertoli cells…. u Sperm cells (1N)

38. EGG

39. Egg Facts u Largest cell in body u Have 500,000 follicles with immature eggs in them at birth u Only release 400 – 500 over lifetime

40. Oogenesis u As embryo until menopause... u Ovaries u Primordial germ cells (2N) u Oogonium (2N) u Primary oocyte (2N) u Between birth & puberty; prophase I of meiosis u Puberty; FSH; completes meiosis I u Secondary oocyte (1N); polar body u Meiosis II; stimulated by fertilization u Ovum (1N); 2nd polar body

41. The female pattern u Estrous cycles/estrus (many mammals) u Menstrual cycle (humans and many other primates): u Ovarian/Menstrual cycles~ follicular phase ~follicle growth ovulation ~ oocyte release luteal phase ~ hormone release

42. Ovarian cycles 1. Hypothalamus registers low levels of progesterone and estrogen  secretes GnRH  anterior pituitary secretes a little FSH/LH 2. FSH  stimulates follicle to complete meiosis I and to release estrogen (levels start to rise) 3. Estrogen  stimulate the Ant. Pit. to release large amounts of LH (spike) (+)  causes ovulation 4. LH  stimulates corpus luteum to release progesterone and estrogen  high levels inhibit the hypothalamus

43. Menstrual Cycle 1. Rising estrogen (estradiol) levels  stimulate endometrium to thicken 1.Follicular phase – proliferative phase 2. Estrogen and progesterone from the corpus luteum  stimulates further thickening 1.Luteal phase – secretory phase 3. Corpus luteum disintegrates  lower levels of estrogen and progesterone  arteries in endometrium to constrict  menstruation

44. Pregnancy u If an embryo implants, it secretes hCG (human chorionic gonadotropin) u hCG acts like LH  stimulates estrogen and progesterone secretion  endometrium stays intact u Pregnancy tests look for presence of hCG in urine

45. Ovulation

46. Corpus Follicle Luteum Estrogen/ Ovulation Progesterone Endometrium thickens

47. Irregular periods u Caused by stress, diet, too much exercise, drugs, sex, new cycle, endocrine imbalance, cold or flu, anxiety about pregnancy, pathogens, endometriosis u Some girls will miss cycles as their body adjusts

48. Before Birth u Fertilization u Fertilization – 1) Occurs in the Fallopian Tubes when sperm meets egg 2) Enzymes in the sperm’s head eat away at the egg’s outer covering and allow the sperm to enter 3) The egg’s membrane changes its electrical charge so that no other sperm can enter

49. Fertilization

50. 1) After fertilization, the zygote (egg and sperm combined) moves to the uterus and implants in the uterine wall 2) This zygote will now develop into the embryo 3) The embryo is connected to the uterus by the umbilical cord which allows passage of nutrients and wastes Implantation

52. Facts u According to the CDC, 65% of high school students will have sex before graduation u A sexually active teenager who does not use contraceptives has a 90% chance of becoming pregnant within one year. u Every year 3 million teens--about 1 in 4 sexually experienced teens--acquire an STD.

53. STD facts u In a single act of unprotected sex with an infected partner, a teenage woman has a 1% risk of acquiring HIV, a 30% risk of getting genital herpes and a 50% chance of contracting gonorrhea u Chlamydia is more common among teens than among older men and women; in some settings, 10-29% of sexually active teenage women and 10% of teenage men tested for STDs have been found to have chlamydia. u You can get STD’s from any kind of sex

54. Pregnancy facts u Each year, almost 1 million teenage women--10% of all women aged 15-19 and 19% of those who have had sexual intercourse--become pregnant. u 6 in 10 teen pregnancies occur among 18-19 year-olds. u No contraception is 100% safe

56. Fetal Development u First Trimester 1) All body systems are present by the eight week 2) Heart begins to beat on the 25 th day 3) Baby is most sensitive to outside influences (alcohol, drugs, smoking) 4) Sex organs form 5) Embryo is now called a Fetus

57. First Trimester Fetus

58. u Second Trimester 1) Rapid growth at the beginning of this trimester 2) Fetus can survive independently outside of the uterus but the likelihood of survival is low (20 weeks)

59. Second Trimester Fetus

60. u Third Trimester 1) Fetus is fully developed and is ready to survive outside of the uterus 2) It kicks, stretches, and moves freely inside the mother (similar to an astronaut in space) 3) Fetus also rotates so that its head is down in time for birth

61. Third Trimester Pic

62. Genetic Counseling u Counseling 1) Trained professionals show prospective parents the probabilities that their children will have certain genetic disorders 2) Usually happens before conception u Prenatal Testing 1) Amniocentesis – a long needle is passed through the mother’s stomach to withdraw a small amount of the fluid surrounding the fetus 2) Tests on this fluid can predict whether the child will have a certain genetic disorder 3) May cause injury to the fetus and/or mother

63. Amniocentesis

64. Birth u Three Phases Dilation of the Cervix 1) Dilation of the Cervix – cervix opens or dilates so the baby can pass through. Can last up to 24 hours -Labor – physical changes a mother goes through give birth

65. Birth (cont.) Expulsion of the baby 2) Expulsion of the baby – Involuntary muscle contractions push the baby through the dilated cervix. The mother aids this process by contracting her abdominal muscles in unison with the uterine contractions. -This stage lasts from 20 minutes to 1 hour

66. Birth (cont.) Placental Stage Afterbirth 3) Placental Stage – 10 to 15 minutes after birth the placenta separates from the uterine wall and is expelled along with the remains of the embryonic membrane. This is known as the Afterbirth.

67. Growth and Aging 1) Infancy (0-2years) – characterized by tremendous growth, infants learn to control their limbs, sit, walk, crawl, and talk 2) Adolescence – onset of puberty, reach full physical maturity 3) Adulthood – metabolism and digestion slow, skin loses elasticity, hair turns white, bone becomes thinner, vision and hearing diminish

68. Post-ovulation

69. Embryonic & fetal development u Gestation ~ pregnancy u 1st trimester: u organogenesis u fetus (week 8; all adult features) u HCG hormone (menstruation override; pregnancy test detection) u Parturition ~birth u Labor ~uterine contractions u Lactation ~prolactin & oxytocin