1. Reproduction & Development in Humans

2. What are the three main functions of the human male reproductive system?

3. The male reproductive system performs two major functions:
1) The production of sperm cells
2) The production of the male hormone testosterone
3) The deposition of sperm cells
within the female reproductive tract

4. Male Reproductive System
Vas deferens c
Glands d
Epididymis
Urethra A
Scrotum F
Penis e
Testes b

5. Male Reproductive System
1. Urinary bladder
2. Seminal Vesicles
3. Vas Deferens
4. Cowpers gland
5. Urethra
6. Penis
7. Epididymis
8. Testis
9. Scrotum
10. Prostate gland

7. Why are the testes held outside the body cavity?
Scrotum

8. Sperm production occurs in the testes.
The testes are located in the scrotum where the temperature is 1-2 degrees Celsius cooler than normal body temperature (37 ºC).
This provides the optimum temperature for production & storage of sperm.

9. Testis

10. Sperm duct (vas deferens)
Urethra

11. The urethra is a tube contained within the penis.
The sperm travel through it on their way out of the male’s body during ejaculation

12. Glands secrete a liquid into these tubes.
The liquid serves as a transport medium for the sperm which is an adaptation for life on land.
This liquid and the sperm cells constitute semen.

13. What is the function of the penis?

14. The penis is a structural adaptation for internal fertilization.

15. Penis
Urethra

16. Prostate gland
Seminal vesicle

17. What are the four main functions of the human female reproductive system?

18. Female reproductive system
4 major functions:
1) The production of egg cells
2) The production of the female hormones estrogen and progesterone
3) Site for the deposition of sperm cells and fertilization of egg
4) Support the development of the embryo/fetus

19. Female Reproductive System
Oviduct E
Ovary
Egg C B
Uterus
Vagina A D

20. Female Reproductive System
1. Vertebrae
2. Oviduct
3. Ovary
4. Uterus
5.Urinary bladder
6.Pubic bone
7.Cervix
8.Anus
9.Vagina
10. Urethra

21. Ovaries

22. Follicles

24. oviduct
cleavage of embryo
fertilization
implantation
egg moves
down oviduct
uterus
ovulation
Sperm deposited in vagina

27. Female Reproductive System
Ovaries are paired structures located within the lower portion of the body cavity.
Ovaries produce eggs (ova) in tiny cavities called follicles.

29. Follicles

30. Ovaries

31. Ovaries

32. 2) What is the function of the scrotum?
1) The _____ releases an egg each month, and this process is known as _______.
2) What is the function of the scrotum?
3) What is a follicle?

33. Following ovulation (release of the egg from the ovary), the egg cell is transported through an oviduct (fallopian tube) to the uterus.

34. Fallopian tubes (oviduct)
Uterus

37. At the lower end of the uterus, known as the cervix, is a muscular tube, the vagina.  
The vagina receives the sperm from the male and is also the birth canal.

38. Cervix
Vagina

39. Usually only one egg is released at the time of each ovulation.
At the birth of a female, all of the potential eggs that she will ovulate are present in immature form.
Usually only one egg is released at the time of each ovulation.

40. In addition to eggs, the ovaries also produce the female sex hormones estrogen and progesterone.

41. 2) List the female sex hormones.
“Do now” Friday
1) The _____ releases an egg each month, and this process is known as _______.
2) List the female sex hormones.
3) Name the milk-producing gland.

42. The hormones also have a coordinating role in the menstrual cycle.
These regulate the development of secondary sex characteristics such as the development of the mammary glands (breasts) and the broadening of the pelvis.
The hormones also have a coordinating role in the menstrual cycle.

44. 1) What are the 4 stages of the menstrual cycle?
“Do now” Tuesday
1) What are the 4 stages of the menstrual cycle?
1) The menstrual cycle begins at _____ & ends at ______.
3) Where does fertilization occur?

45. “Do now” 3-17-04 3) Where does fertilization occur?
1) The menstrual cycle begins at _____ & ends at ______.
2) How long is the menstrual cycle?
3) Where does fertilization occur?

46. Menopause is the permanent cessation of the menstrual cycle.
begins at puberty and ceases at menopause.
Menopause is the permanent cessation of the menstrual cycle.

47. The duration of this cycle is approximately 28 days but may vary considerably and may be interrupted by pregnancy, illness, and other factors.

48. The menstrual cycle consists of 4 stages:
1) Follicle stage involves the maturation of an egg within the follicle & estrogen secretion.

49. Estrogen initiates vascularization (thickening by blood tissue) of the uterine lining.

50. 2) Ovulation is the release of an egg from the follicle.
3) Corpus luteum stage occurs when the corpus luteum forms from the follicle following ovulation.

51. 1) What are the 4 stages of the menstrual cycle?
“Do now” Tuesday
1) What are the 4 stages of the menstrual cycle?
2) The menstrual cycle begins at _____ & ends at ______.
3) List the 4 hormones involved in the menstrual cycle.

54. Ovulation

55. It secretes progesterone which enhances the vascularization of the uterine lining.

56. is the periodic shedding of the thickened uterine lining.
4) Menstruation
is the periodic shedding of the thickened uterine lining.
Generally, menstruation lasts for a few days and occurs when fertilization does not take place.

57. Role of Hormones in the Menstrual Cycle.
The reproductive cycle of the human female involves the interaction of the hormones from the hypothalamus, pituitary gland and ovaries.

58. During the menstrual cycle, under the influence of the hormones from the hypothalamus, the pituitary gland releases hormones (FSH and LH) which influence the functioning of the ovaries.

59. 1) What are the 4 hormones involved in the menstrual cycle?
“Do now” Monday
1) What are the 4 hormones involved in the menstrual cycle?
2) Explain the corpus luteum stage.

60. FSH LH
Pituitary gland
Ovary
STOP!
Progesterone
Estrogen

61. FSH stimulates follicle growth and the ovary to produce estrogen.

62. LH stimulates the growth of the corpus luteum (in the ovary) to secrete progesterone which inhibits estrogen production.

63. Estrogen causes the release of FSH to be stopped.
The ovaries, in turn, secrete hormones (estrogen and progesterone) which produce changes in the uterus.
Estrogen causes the release of FSH to be stopped.

64. An increase in progesterone causes a reduction in the production of FSH and LH.

65. In addition, the hormones from the ovaries regulate the secretion of hormones by the pituitary gland and the hypothalamus (negative feedback mechanism).

66. Usually occurs in the upper one third of the oviduct.
Fertilization
Usually occurs in the upper one third of the oviduct.
If the egg is not fertilized within approximately 24 hours after ovulation, it deteriorates.

67. If fertilization occurs, cleavage of the fertilized egg (zygote) begins in the oviduct, and six to ten days later, the resulting embryo may become imprinted in the uterine lining.

68. At this stage of development, the yolk of the egg has been depleted.
But with implantation, the embryo can obtain nutrients from the uterus.

69. If more than one egg is released and fertilized, multiple births may result.
Identical twins develop from one zygote which separates during cleavage.

72. Fraternal twins develop from two eggs, each fertilized by separate sperm cells.

73. 1) Explain how the 4 hormones work together in the menstrual cycle.
“Do now”
1) Explain how the 4 hormones work together in the menstrual cycle.
2) Explain how identical & fraternal twins are created.

74. The technique of in vitro fertilization and subsequent implantation that has been perfected in animals has now been applied to humans with some degree of success.

75. In vitro fertilization is commonly called the "test tube baby" process.

76. Prenatal development includes the following processes:
Cleavage occurs in the oviduct.

77. Gastrulation usually occurs after the embryo is implanted in the uterus.  
Differentiation and growth result in the formation of specialized tissues and organs from the embryonic layers of the gastrula.

78. Prenatal development is dependent upon several structures that are similar in the structures found inside of the externally developing egg. ‑

79. The placenta is the "connection" between the mother and the developing embryo which allows nutrients, respiratory gases, and wastes to be exchanged.

80. * Note that there is no direct connection, therefore, there is no mixing of blood between the embryo and the mother.

81. Substances move between the two separate circulatory systems by active and passive transport.

82. The amnion is the membrane that surrounds the embryo and contains the amniotic fluid which protects the developing embryo from shock and temperature changes.

84. The umbilical cord ("life line") holds the blood vessels that carry materials between the embryo and the placenta.

85. Umbilical cord

86. The process involved in prenatal development is dependent upon the supplying of a proper balance of nutrients to the developing embryo.

87. Good nutrition during pregnancy for both the mother and the developing fetus is essential for proper and safe development.

88. usually occurs after a gestation period of approximately nine months.
Birth
usually occurs after a gestation period of approximately nine months.

89. During birth, strong contractions of the uterine muscles (labor) forces the baby through the cervix and vagina (birth canal) and to the outside of he mother's body.

90. The expulsion of the placenta occurs after the delivery of he baby.

91. Postnatal Development
Development continues with various parts of the body growing at different rates.

92. Although the development of the organism is often assumed to conclude with the mature adult, it actually continues throughout the life of the organism and terminates with death.

93. The term aging is applied to the complex developmental changes that occur naturally with the passage of time.
The cause or causes of the aging process are still not fully understood.

94. It appears that the aging process results from the interplay of hereditary and environmental factors.
One recent definition of death is the irreversible cessation of all brain functions.

95. Twinning rates 2.6% of births in 1997 were twins One in 50,000 births results in conjoined twins. Fraternal twinning by racial background:     African 1 in 70 births     Caucasian 1 in 88 births     Japanese 1 in 150 births     Chinese 1 in 300 births