1. Human reproduction

2. Male and female gametes Cells fuse to form a fertilised egg
23 chromosomes
Egg
Sperm
The human life cycle
Cells fuse to form a fertilised egg
46 chromosomes

3. VIRUS (0.05 to 0.1 microns) BACTERIA RED BLOOD CELL (5 microns) OVUM
SIZE COMPARISONS
10 microns (0.01mm)
VIRUS
(0.05 to 0.1 microns)
BACTERIA
100 microns
OVUM
(0.5 to 1.5 microns)
RED BLOOD CELL
(5 microns)
WHITE BLOOD CELL
(5 to 8 microns)
SPERM
(60 microns)

4. Gland for making seminal fluid
Bladder
Gland for making seminal fluid
Prostate Gland
Sperm duct
Penis
Scrotum
Testis

5. Male Gamete – Sperm
vesicle contains enzymes involved in penetration of ovum during fertilization
head
Nucleus containing DNA
middle piece
mitochondria which release energy during respiration
tail brings about movement

6. Sperm Sperm carry a nucleus in the head
300 million produced during intercourse
Released in a liquid called semen

8. Secondary Sexual Characters
During puberty
boy :
hair in pubic and facial regions
larynx growth, voice break
muscular development
girl :
breast development
hips widen
more fat under skin
menstruation

10. Menstrual Cycle Generally about every 28 days
The uterus lining becomes thickened 14 days after menstruation to prepare for the fertilized ovum to implant in it
Uterus :
thickening of lining
menstruation (discharge of lining if no fertilization)

11. Menstrual Cycle Day 1 - 5 Menstruation starts
Uterus lining decreases in thickness to a minimum

12. Menstrual Cycle
Day
Lining becomes thicker with increased blood supply
Day 14 : ovulation

13. Menstrual Cycle
Day
Lining remains thick to ready for implantation of fertilized ovum

14. Menstrual Cycle Day 28 No implantation of fertilization ovum
Uterus lining breaks down – menstruation starts

15. Fertilization oviduct ovary uterus cervix vagina 1st day 2nd day
6th day
3rd day
cervix
vagina
4th day

16. sperms

18. Events Happened after fertilization
Sperms reach the upper part of the fallopian tube
Egg is fertilized at the fallopian tube
Fertilized egg is carried to the uterus
After reaching the uterus, the embryo fixed firmly onto the thick uterus wall
– Implantation

19. Ovulation and fertilization

20. Placenta

21. Functions of the Placenta
The placenta is an organ that is made up of tissues from the mother and the baby.
It allows food and oxygen to pass from the mother to the baby.
It allows waste to pass from the baby to the mother for removal.
Harmful substances such as drugs and alcohol can also pass in to the baby and cause damage.

22. Embryo at 2 weeks

23. Embryo at 4 weeks

24. Embryo at 8 weeks

25. Development of Human Foetus
uterus
foetus
placenta
umbilical cord
amniotic fluid

26. Functions of Uterus During embryo development During birth of baby
– Protect the embryo
– Provide a constant environment for the embryo to develop
– Allow placenta to attach on
During birth of baby
– Push the baby out by muscular contraction

27. Birth
At the end of the pregnancy the womb begins to contract and labour begins.
These contractions cause the amniotic sac to burst and the amniotic fluid to be released – “the breaking of the waters”
The cervix and the vagina expand or dilate.
The contractions of the womb push the baby out through the vagina and it is born.
The umbilical clamped and cut.
The contractions of the womb continue and they push out the placenta and umbilical cord. This called the afterbirth.

28. Labour and birth

29. Contraception
Contraception is any method that tries to prevent fertilisation or pregnancy occur.
There are 2 types of contraception
Natural methods – abstinence and avoiding sex during the fertile period.
Artificial methods – artificially preventing sperm meeting egg or implantation.

30. Artificial Methods Female Male Tying or cutting of fallopian tubes
Taking “the pill” – prevents ovulation
IUD (the coil) – prevents implantation
Diaphragm (the cap) – prevents the sperm entering the uterus/fallopian tubes
Male
Vasectomy – cutting the sperm duct, no sperm released into vagina
Condom – prevents sperm being released into vagina

31. Contraception