1. Unit 2 - Physiology and Health
Reproductive organs and hormonal control

2. Reproductive Organs and Gametes
Prior Knowledge
Reproductive organs produce gametes
Male gamete- sperm
Female gamete- egg/ova
Male reproductive organ- testes
Female reproductive organ-ovary

3. nucleus containing DNA
Sex cells – sperm
In males, the sex cells are called sperm.
tail
middle piece
head
cell membrane
nucleus containing DNA
Sperm are produced in sex organs called testes.

4. nucleus containing DNA
Sex cells – egg
In females, the sex cells are called eggs.
nucleus containing DNA
cytoplasm
membrane
jelly coat
Eggs are produced in sex organs called ovaries.

5. Learning Intention:
To learn about the structure and function of reproductive organs and gametes and their role in fertilisation
Success Criteria:
By the end of the lesson I should be able to
State that gametes production takes place in the testes in males.
Explain the role of the seminiferous tubules.
Explain the role of the interstitial cells.
Explain the role of testosterone in negative feedback.
Explain the role of the prostate gland and seminal vesicles
State that gametes production takes place in the ovaries in females.
State that each ovum is surrounded by a follicle which secretes hormones.
State that mature ova are released during ovulation.
State where fertilisation takes place and that a zygote is formed.

6. Production of Gametes
A germ line is the sex cells (eggs and sperm) that are used by sexually reproducing organisms to pass on genes from generation to generation.
Gametes are produced by germline cells

7. MALE REPRODUCTIVE SYSTEM
BLADDER
URETER
PUBIC BONE
SEMINAL VESICLE
PROSTATE GLAND
RECTUM
URETHRA
ERECTILE TISSUE
COWPER’S GLAND
VAS DEFERENS
PENIS
EPIDIDYMIS
SCROTUM
TESTIS

8. Revision: The male reproductive system

9. TESTES
SEMINIFEROUS TUBULE
INTERSTITIAL CELLS

10. TESTES Seminiferous tubules – produce sperm
Interstitial cells– secrete testosterone
Interstitial cells

11. Accessory Glands Seminal vesicles and the prostate gland
Semen consists of 10% sperm and 90% fluid and as sperm pass down the ducts from testis to penis, (accessory) glands add various secretion
The prostate gland and seminal vesicles secrete fluids that maintain the mobility and viability of the sperm. This fluid is called semen
Seminal vesicles secrete a fructose rich liquid, which provides energy for the mobility of the sperm
The liquid also contains hormone like compounds (Prostaglandins) which stimulate contractions of the female reproductive tract
Prostate gland secretes a thin lubricating liquid containing enzymes which regulate the viscosity of semen

12. FEMALE REPRODUCTIVE SYSTEM
OVIDUCT
ENDOMETRIUM
OVARY
UTERUS
CERVIX
VAGINA

13. Revision. The female reproductive system

14. THE OVARIES
The ovaries contain immature ova in various stages of development
Each ova is surrounded by a follicle that protects the developing ovum and secretes hormones
Mature ova are released into the oviduct where they may be fertilised by sperm to form a zygote

15. GRAAFIAN FOLLICLE

16. Male or female?

17. Roles of the reproductive system

18. Human Ovulation

23. Fertilisation and implantation

24. Summary - You should know
The structure and function of reproductive organs and gametes and their role in fertilisation.
Gamete production in the testes. The roles of seminiferous tubules, interstitial cells, testosterone, prostate gland and seminal vesicles.
Gamete production in the ovaries to include maturation of ova and the development of a follicle. Site of fertilisation in the oviduct and zygote formation.

25. Hormonal Control

26. Learning Intention:
To learn about Hormonal control of reproduction
Success Criteria:
By the end of the lesson I should be able to
State that the pituitary gland is stimulated to release FSH, LH (females) or ICSH (males) by the releaser hormone produced in the hypothalamus.
Explain that in males FHS promotes sperm production and that ICSH stimulates the production of testosterone.
State that testosterone also stimulates sperm production and activates the prostate gland and seminal vesicles.
Describe the negative feedback mechanisms for controlling testosterone.
Explain that in females, FSH stimulates the development of the Graafian follicle while LH triggers ovulation.
State that FSH and LH trigger the ovaries to produce oestrogen and progesterone.
Eexplain the role of oestrogen and progesterone in the menstrual cycle.
Describe the mechanisms of negative feedback leading to menstruation.

27. Hormones
Hormones are chemical messengers produced by cells that bind to receptors on the plasma membrane of other cells or enter other cells and alter the metabolic function of these cells.
In response to a signal from the brain, hormones are secreted directly into the blood by the glands that produce and store them. These glands make up what is known as the endocrine system
The testes and ovaries, or "gonads", are endocrine glands.
In males, testes produce sperm and secrete the male sex hormone testosterone;
in females, ovaries produce eggs and the female hormone oestrogen.
It is these hormones that determine secondary sex characteristics like muscle mass and facial hair. They also help to orchestrate sperm production, menstruation and pregnancy.

29. Hormonal Onset of Puberty
At puberty the hypothalamus secretes a releaser hormone that targets the pituitary gland
Releaser hormones cause the release of other hormones to start and stop
The pituitary gland is stimulated to release
follicle stimulating hormone (FSH)
Luteinising hormone (LH) in women
Or interstitial cell stimulating hormone (ICSH) in men
These hormones control the onset of puberty

31. Discuss in pairs what changes happen to the body during puberty?
Produce two spider diagrams illustrating the changes that happen at puberty in both males and females.
Question : What is the role of the hypothalamus and the pituitary gland in puberty?

32. Hormonal Control of Sperm Production

33. Male Hormones
FSH (follicles stimulating hormones) promotes spermatogenesis in seminiferous tubules
ICSH (Interstitial cell-stimulating hormone) stimulates interstitial cells to produce male hormones (eg testosterone)
Testosterone also stimulates sperm production and activates the prostate gland and seminal vesicles
FSH and ICSH exhibit negative feedback control on the pituitary gland decreasing the level of testosterone produced by the interstitial cells

34. NEGATIVE FEEDBACK CONTROL
High levels of testosterone have an inhibitory effect on the pituitary gland
Inhibits secretion of FSH and ICSH
Thus, levels of testosterone fall
Inhibitory effect on pituitary ceases
FSH and ICSH secretion increases
Levels of testosterone increase

35. SELF REGULATION OF TESTOSTERONE
PITUITUARY GLAND
Stimulates
Inhibits
Testosterone
FSH
ICSH
SEMINIFEROUS TUBULES
INTERSTITIAL CELLS

36. 1. Analyse the diagram in pairs and explain what is happening.
2.Devise and complete a table to show hormones and their functions
Hormone
Function
= stimulates
= inhibits

37. Essay Question
Describe the influence of hormones on the testes.

38. Hormonal Control of the Menstrual Cycle

39. MENSTRUAL CYCLE Takes on average 28 days
Menstruation is day 1 to 5 of the cycle
Endometrium starts to repair
Ovulation day 14
Endometrium thick and spongy
Menstruation in absence of fertilised egg
Consists of 2 phases-Follicular phase & Luteal phase

41. Follicular Phase
FSH
Causes development of follicles in ovary
Stimulates secretion of oestrogen by the follicle
oestrogen stimulates proliferation of the endometrium preparing it for implantation and affects the consistency of cervical mucus making it easier for sperm to penetrate

42. Luteal Phase LH
Peak levels of oestrogen stimulate a surge in the secretion of LH which triggers ovulation
Causes Graafian follicle to rupture (ovulation)
Causes development of the corpus luteum from the follicle
Stimulates the corpus luteum to secrete progesterone

43. Progesterone promotes further development and vascularisation of the endometrium preparing it to receive a blastocyst if fertilisation occurs. Ovum dies after 36 hours

44. Negative Feedback Effect of Ovarian Hormones on the Pituitary
High levels of oestrogen and progesterone have an inhibitory effect on the pituitary gland
Decrease the levels of FSH and LH which prevents further follicles from developing
The lack of LH leads to degeneration of the corpus luteum
A drop in progesterone leads to menstruation

46. Questions Name three reproductive processes that hormones control
Name two female hormones produced by the pituitary
What does testosterone do?
What does high levels of oestrogen do to the cells lining the cervix?
Name the two hormones that progesterone inhibits

47. Answers
1. Name three reproductive processes that hormones control the onset of puberty, sperm production, the menstrual cycle 2. Name two female hormones produced by the pituitary FSH and LH 3. What does testosterone do? Stimulates sperm production and activates the Seminal Vesicles and Prostate Gland to produce secretions 4. What does high levels of oestrogen do to the cells lining the cervix? High levels of oestrogen stimulates the cells lining the cervix to secrete a watery mucus easily penetrated by sperm 5. Name the two hormones that progesterone inhibits FSH and LH by the pituitary gland

48. Critical skills activity
Your task is to find out about the role of the four female hormones and present this information in a form that others can learn from. This could be a poster, a PowerPoint presentation, a leaflet or another presentation form.
You should include:
accurate information
labelled diagrams if appropriate
information about the four female hormones:
their roles in the menstrual cycle
where they are produced
what order they occur in in each menstrual cycle.
Each person in your group should be able to explain the role and function of each hormone.

49. Essay Question
Describe the menstrual cycle under the following headings:
The follicular phase (4 marks)
The luteal phase (6 marks)
Extension – Hormones Blind Date

50. Hormonal control of the menstrual cycle

51. Lasts approximately 28 days
The first day of the menstruation is regarded as day 1 The cycle takes place in two phases – the first or Follicular Phase and the second or Luteal Phase Follicular Phase (day 114) During the first half of the cycle the pituitary gland releases FSH FSH has two effects

52. FSH – 2 effects 1. it causes a follicle to develop in the ovary
2. it stimulates the wall of the follicle and the tissues of the ovary to secrete the hormone oestrogen
The immediate effect of oestrogen is to bring about healing and repair of the uterine wall
In the course of the next 2 weeks the level of oestrogen in the body builds up

53. high oestrogen levels
Peak levels of oestrogen stops the pituitary producing FSH and stimulates it to produce a surge in the secretion of LH
The surge in LH triggers ovulation
As stated previously, high oestrogen level affects the consistency of the cervical mucus -the mucus is more easily penetrated by sperm and leads to an increased chance of fertilisation

54. Luteal Phase (day1428)
LH causes the follicle to change into the corpus luteum The corpus luteum secretes a hormone called progesterone Progesterone (and oestrogen) cause the continued proliferation and vascularisation of the endometrium in preparation for receiving a blastocyst During the next 10 days or so the concentration of progesterone inhibits the production of FSH and LH from the pituitary

55. uterus
oviduct
zygote
blastocyst
fertilisation
egg
ovary
implantation

56. 15

58. Menstrual Cycle

59. MENSTRUAL CYCLE Takes on average 28 days
Menstruation is day 1 to 5 of the cycle
Endometrium starts to repair
Ovulation day 14
Endometrium thick and spongy
Menstruation in absence of fertilised egg
Consists of 2 phases-Follicular phase & Luteal phase

60. Inhibition of FSH and LH
Inhibition of FSH and LH – prevents further follicles from developing Stops the ovary producing oestrogen Causes the corpus luteum to degenerate and cease producing progesterone Sudden drop in oestrogen and progesterone causes menstruation to occur

61. Summary FSH and Oestrogen
FSH follicle develops ovary secretes oestrogen Oestrogen Heals and repairs lining At high concentration, oestrogen inhibits FSH and stimulates pituitary to produce LH

62. Summary of LH and Progesterone
LH sudden surge of LH causes ovulation LH changes follicle to corpus luteum Corpus luteum secretes progesterone Progesterone Progesterone and oestrogen cause further proliferation and vascularisation High progesterone inhibits FSH and LH

63. Towards end of cycle
Ovary stops secreting oestrogen Corpus luteum stops producing progesterone No hormones to proliferate lining Menstruation

64. Questions What does the follicle develop into following ovulation?
The menstrual cycle consists of the endometrial phase and the luteal phase? T or F
FSH stimulates the ovary into secreting oestrogen?
Oestrogen stimulates the proliferation of the endometrium?
LH triggers the process of menstruation?
Progesterone inhibits the secretion of FSH and LH by the Ovaries?
Lack of LH leads to degeneration of the corpus luteum?

65. Answers . . . . Corpus luteum False, follicular True False, ovulation
False, pituitary

66. Complete the table . . . . Hormone Site of production
One function of the hormone
Stimulates the development of the follicle
Brings about development of corpus luteum
Stimulates secretion of LH by the pituitary
Promotes vascularisation of the endometrium

67. Answers . . . . FSH Pituitary gland LH Oestrogen Ovary Progesterone
Hormone
Site of production
One function of the hormone
FSH
Pituitary gland
Stimulates the development of the follicle LH
Brings about development of corpus luteum
Oestrogen
Ovary
Stimulates secretion of LH by the pituitary
Progesterone
Promotes vascularisation of the endometrium