1. The means by which we increase in number and fill the earth.
Sexual Reproduction
The means by which we increase in number and fill the earth.

2. Human Reproduction Introduction Puberty Reproductive systems
Fertilisation
Menstrual cycle
Contraception / IVF
Sexually Transmitted Diseases
Premarital sex and abortion

3. Introduction
One characteristic of living organisms is that they can reproduce.
What does ‘reproduce’ mean?
to produce young ones or new individuals
Why is there a need to reproduce?
to replace those that die
to ensure that the species does not become extinct
What would happen if living thing didn’t reproduce?

4. (does not involve the fusion of 2 different reproductive cells)
Asexual
Reproduction
(involves the fusion of different reproductive cells)
Sexual

5. Asexual Reproduction In asexual reproduction there is only one parent.
All offspring are identical to the parent.
They have exactly the same genes.
They are called clones.

6. Sexual Reproduction Involve two parents Have different sex organs
Producing gametes

7. Sexual reproduction involves the fusion of 2 different reproductive cells. What are reproductive cells and where do they come from?

8. (organs producing reproductive cells or gametes)
Gonads
(organs producing reproductive cells or gametes)
Testes Ovaries
produce
produce
Sperm
Ova

9. In higher animals, the testes and ovaries are borne by different individuals.
Hence a mating process is required to allow the meeting of the gametes.
Mating occurs only between physically mature individuals.

10. Fertilisation
During sexual reproduction the sperm and the egg join together.
This is called fertilisation.
A fertilised egg, or zygote, is produced.

11. Fertilisation
External Fertilisation – fertilisation take place outside the body – in water
Internal Fertilisation – fertilisation take place inside the body of the female

12. When does an individual become physically mature?
An individual becomes physically mature when he reaches puberty

13. Puberty Puberty demo around the age of 11 to 13
the time of active growth in humans and other mammals during which the
reproductive organs become functional,
i.e. they start producing sex hormones and gametes
physical changes develop as a result of the secretion of sex hormones
When do girls and boys enter puberty?
around the age of 12 to 14
around the age of 11 to 13
Puberty demo

14. Changes in boys: Changes in girls: 1. physical changes, e.g.
(a) growth of hair
(i) on certain parts of face
(ii) on chest
(iii) in armpits
(iv) at pubic region
(b) “Adam’s apple” appears as the larynx or voice box increases in size,
causing the voice to break and deepen
testes and penis grow bigger
2. Testes start to produce (i) sperm and (ii) male sex hormones (testosterone)
1. physical changes, e.g.
(a) growth of hair
(i) in armpits
(ii) at pubic region
(b) breasts grow bigger
hips become wider and rounder
2. Ovaries start to
(i) produce female sex hormones (oestrogen and progesterone) and
(ii) release mature eggs (ova,
singular: ovum)
Menstruation starts

15. Human reproductive organs

16. The male reproductive system
seminal vesicle
Cowper’s
gland
prostate
gland
seminal vesicle
prostate
gland
sperm duct
spermatic cord
Cowper’s
gland
epididymis
penis
urethra
sperm duct
urethra
testis
epididymis
scrotum
testis
penis
testis
scrotum

17. Sperm

18. The Female Reproductive System
ovary
uterine
lining
oviduct
uterus
oviduct
cervix
ovary
uterus
uterine
lining
urethra
vagina
vagina
cervix
vulva
vulva
urethra

19. Egg /Ovum
egg membrane

20. Comparison of a Sperm and an Ovum
Sperm (male gamete )
Ovum (female gamete)
1. Production
released by the ovaries
produced by the testes
released from puberty
till menopause
produced from puberty onwards
2. Size
about 0.01 to 0.05 mm long
about 0.10 mm in diameter
3. Quantity
only one ovum is released
at each ovulation (once in
about 28 days)
about 500 million sperm are released at each ejaculation during mating
4. Mobility
not capable of movement
capable of movement by itself,
can swim vigorously towards the ovum to fertilise it

21. Sperm (male gamete ) Ovum (female gamete) 5. Structure
divided into 3 parts:
spherical , surrounded by a thin membrane and a layer of jelly
a) Head
- contains large nucleus with little cytoplasm and a sac which contains enzymes that break down part of the egg membrane for penetration during fertilisation
has a nucleus and abundant cytoplasm containing stored food
b) Middle piece
- contains mitochondria that provides
energy for the activity of the sperm
c) Tail (flagellum)
- enables the sperm to swim towards the egg

22. Comparison of Size

23. Internal Fertilisation
Before fertilisation, mating or sexual intercourse must take place

24. Erection of penis
During sexual intercourse, the erect penis is placed / inserted into the vagina of the female

25. Sexual Intercourse
Ejaculation occurs - semen containing sperm (about 500 million are released but only a few hundred reach the oviduct) is deposited / released into the vagina.

26. Ovulation What is ovulation? release of a mature egg from an ovary
occurs about once every 28 days
the egg enters the funnel-shaped opening of the oviduct which carries it to the uterus
fertilisation can occur if the egg meets a sperm in the oviduct

27. Oviducts (fallopian tubes)
Have many tiny hairs (cilia) on inner walls that help to push the ovum along the oviduct as the muscles contract

28. Fertilisation What is fertilisation?
Fertilisation is the fusion of the nuclei of the sperm and the egg.
It occurs in the oviduct.
to penetrate the egg, the acrosome of the sperm releases an enzyme to break down part of the egg membrane
only the head goes in, and the its nucleus fuses with the nucleus of the egg

29. What happens after fertilisation?
when nucleus of egg fuses with nucleus of sperm, the fertilised egg is called a zygote
zygote continues journey through the oviduct and divides to form a ball of cells called the embryo
embryo enters the uterus and attaches itself to the thick uterus lining from which it gets nourishment and oxygen
embryo grows and develops into a fetus

31. Embryonic Development

32. Stages of Menstrual Cycle
Menstruation
Repair and Growth of Uterine Lining
Ovulation
Further thickening of Uterine Lining

33. 1. Menstruation If no fertilisation occurs after ovulation,
ovaries will stop producing hormones
ovum disintegrates
thick lining of uterus breaks down
broken lining, disintegrated egg and some blood flow out through the vagina
– menstrual flow - marking the start of menstruation
menstruation lasts for about 5 days

34. 2. Repair and Growth of Uterine Lining
(after menstruation)
after menstruation, ovaries release oestrogen into bloodstream
oestrogen causes growth and repair of uterine lining and blood capillaries to form within the thick lining - uterine wall becomes thick and spongy with blood vessels again

35. 3. Ovulation occurs about the 14th day of the menstrual cycle
if fertilisation occurs - the female becomes pregnant
if no fertilisation occurs - menstruation occurs again 14 days after ovulation
for married couples who want to have children, sexual intercourse during period of ovulation is more likely to result in pregnancy

36. 4. Further thickening of Uterine Wall
after ovulation, ovary secretes progesterone into bloodstream
progesterone causes uterine lining to thicken further and becomes vascularised (contain many blood capillaries) - ready for implantation of embryo
if there is no fertilisation, uterine lining breaks down and menstruation starts again

37. Menstrual Cycle Start Uterine lining grows and thickens
Repair and growth of uterine lining
Uterine lining thickens further and becomes more vascular, preparing for implantation
Uterine lining breaks down and is discharged
Start

38. Contraception
refer to birth control
due to over-population

39. Family Planning by a couple refers to
limiting the number of children to have and
spacing out the arrival of children
made possible by practising
birth control or contraception
which prevents
ovulation or
fertilisation (sperm and egg cannot meet) or
a fertilised egg from being implanted in the uterine lining

40. The Fertile and Infertile phases
an ovum released during ovulation can live for days before it dies
sperm released into the female reproductive system can live for days
time from day 11 to fertile phase because fertilisation can occur during this period
rest of the days in the menstrual cycle - infertile phase because fertilisation is usually not possible during this period

41. Irregularities in menstrual cycle can be caused by:
However, a woman’s menstrual pattern may not be a reliable indicator of her fertility.
Irregularities in menstrual cycle can be caused by:
 stress  emotional disturbances  mental fatigue  illness  unbalanced diet, malnutrition

42. Contraceptive Methods
Temporary Methods Permanent Methods
(couples can have children when they stop using the methods)
(couples cannot have any more children in future, very difficult to reverse)

43. Temporary Contraceptive Methods
Use of spermicides
chemicals to kill sperm, in form of gels, aerosol foam or tablets, placed in vagina before intercourse, used together with diaphragm or condom
prevent fertilisation

44. 2. Use of contraceptive pills
contain a hormone (progesterone)
prevent ovulation
- prescribed by doctor

45. 3. use of contraceptive devices, such as
condoms and diaphragms
(prevent sperm from meeting the egg and so prevent fertilisation)
                           

46. Condom
a rubber tube worn over erect penis to collect the semen, so no sperm can enter vagina
can also prevent spread of sexually-transmitted diseases since impermeable to bacteria and viruses

47. Diaphragm - dome-shaped rubber cap with elastic rim
inserted into top of vagina and placed over cervix
prevent sperm from entering the uterus
- spermicide may be used together with it

48. 3. use of contraceptive intra-uterine devices
- a coil or loop of plastic or metal, inserted into uterus
- prevents implantation of embryo in the uterine lining
- needs to be fitted by a doctor

49. Permanent Contraceptive Methods
vasectomy (male sterilisation)
 - a section from the middle of each sperm duct is cut and ends tied - prevents flow of sperm to urethra - semen released contains only fluid from sex glands   

50. Permanent Contraceptive Methods
ligation (female sterilisation)
- mid-portion of each oviduct is cut and ends tied - prevents released egg from travelling through oviduct to reach uterus

51. Sexually Transmitted Diseases (STDs)
diseases passed on from an infected person to another person through sexual intercourse
dangerous - because infected person usually feels and looks healthy during early stage of infection
babies born to infected mothers may be infected too

52. Gonorrhoea Syphilis AIDS Sexually Transmitted Diseases (STDs)
(Acquired Immune Deficiency Syndrome)

53. 1. Gonorrhoea caused by a type of bacteria
can be passed on by an infected person
- to his or her partner, during sexual intercourse - to a baby during birth
baby can become blind if bacteria enter eyes during birth

54. Signs and Symptoms of Gonorrhoea
pain when passing urine
for men - a discharge of pus from the penis
for women - lower abdominal pain from infection of the oviducts which can lead to sterility
- no symptoms in women in early stages
can lead to sterility in men and women if not treated

55. Gonorrhoea

56. Gonorrhoea
blind due to gonorrhoea

57. Treatment of Gonorrhoea
can be cured by a course of antibiotics such as penicillin

58. 2. Syphilis caused by a type of bacteria
spread by an infected person to his or her partner, during sexual intercourse
disease can be passed on from an infected woman to her fetus during pregnancy
- baby born with congenital syphilis, may suffer from deafness and eye defects, have abnormal teeth, bones and joints

59. Signs and Symptoms of Syphilis
Earlier stage
- painless sores (on lips, tongue, penis, vagina, cervix- usually heals in a week or two, even without treatment)
- non-itchy skin rash
Later stages
- heart failure
- blindness
- bone / joint deformity
- paralysis, insanity and even death

60. Syphilis

61. Syphilis

62. Syphilis

63. Syphilis

64. Treatment of Syphilis
can be cured by a course of antibiotics such as penicillin

65. Treatment for Gonorrhoea and Syphilis
full course of antibiotics, such as penicillin
infected person to refrain from sexual intercourse
tracing contacts whom the patient
has had intercourse and treating them

66. Prevention and Control of Gonorrhoea and Syphilis
- male to wear condom
- discourage promiscuous sexual behaviour and keep to one sex partner

67. 3. Acquired Immune Deficiency Syndrome (AIDS)
caused by a virus, Human Immuno-deficiency Virus (HIV)
destroys body’s immune system so infections which are normally mild may prove to be fatal

68. Ways in which HIV can be transmitted
- sexual intercourse with an infected person
- sharing of HIV-contaminated needles when abusing drugs
- transfusion of blood contaminate with HIV
- during pregnancy or childbirth, when a HIV-positive mother passes the virus to her child

69. Signs and Symptoms
- no symptoms at first but
- after a few months may develop symptoms such as
- tiredness - loss of appetite - loss of weight - prolonged fever - night sweats - skin rash - swollen lymph glands - persistent diarrhoea - lowered resistance to infections
- after several years, immune system weakens

70. AIDS (final stage of HIV infection) - within 8-10 years for half of those infected
complete breakdown of body’s immune system against infections
diseases include - pneumonia - Kaposi’s sarcoma (cancer of the blood vessels) - persistent diarrhoea - brain infection - tuberculosis

71. AIDS

72. Prevention and control
- keep to one sex partner
male to wear condoms to reduce the risk of infection
avoid sharing items that are likely to break the skin and be contaminated with blood
- go to reliable operators for acupucture, ear-piercing or tattooing, making sure instruments are sterilised or insist on using disposable instruments

73. Educating the public
Never share needle
Avoid sex with prostitutes /
Stay with one STD-free partner
Always use a condom
Destroy all contaminated blood

74. Treatment of AIDS drug AZT can slow down the course of the disease
there is no cure for AIDS
Chemical Name: Azidothymidine Generic Name: Zidovudine Nick Name: AZT Brand Name: Retrovir ® (Retrovis ®) Manufacturer: Glaxo-SmithKline

75. Premarital Sex and Abortion
Premarital sex is having sexual intercourse before marriage
Abortion is the deliberate ending / termination of pregnancy through a medical procedure and involves the removal of the foetus from the mother’s uterus

77. Abortion is safer and easier if it is done in the first 3 months of pregnancy
Termination of a pregnancy can be risky if it is not performed by trained medical personnel, under safe and proper conditions

79. Main medical reasons for abortion
· The baby may be born deformed, with inherited diseases or mental abnormality.
· The pregnancy may affect the mother’s health.
The baby may be infected with sex transmitted diseases.
· The pregnancy may be the results from contraceptive failure or rape.

80. -END-