1. In This Section We Will Be Studying The Following Topics:
REPRODUCTION
In This Section We Will Be Studying The Following Topics:
How does a new life start?
Fertilisation: When egg and sperm meet.
Male and female reproductive organs.
The changes in puberty.
The menstrual cycle and periods.
Pregnancy and the placenta.
How do twins and multiple births happen?
What are the needs of a new baby?
Making milk.

2. HOW DOES IT HAPPEN?
Organisms need to reproduce so that they can produce more individuals (offspring).
The way the egg and sperm meet is different in different living things. We have to MATE to reproduce sexually.
This usually means getting the egg and sperm very close together. In humans the penis is placed into the vagina.

3. FERTILISATION
Fertilisation happens when the nucleus of the sperm cell fuses together with the nucleus of the egg cell (ovum).
The male body is adapted to produce sperm (the male sex cells) in the testes.
The female body is adapted to produce eggs (the female sex cells) in the ovaries.
TASK
The female body is also adapted to carry the baby for the full 40 weeks of development.
Can you find out the time it takes for other mammals to have a baby?

4. Only one sperm cell can penetrate (get inside) the egg.
HUMAN REPRODUCTION
Look at the strip above, and put the captions below into the correct order. A B C D E F
The genetic information from the mother has now joined with the genetic information from the father. The zygote then begins to divide. The cell splits into 2.
When the sperm enters the egg its tail falls off. The nucleus of the sperm then joins with the nucleus of the egg. This is the zygote.
The cell continues to divide to form a mass of cells called the blastocyst. This implants into the wall of the uterus.
Only one sperm cell can penetrate (get inside) the egg.
The cell then splits into 4, then 8, then 16. This process is called growth.
Sperm swim up through the uterus, into the oviduct where they meet the egg.

5. HUMAN REPRODUCTION
Sperm swim up through the uterus, into the oviduct where they meet the egg.
Only one sperm cell can penetrate (get inside) the egg.
When the sperm enters the egg its tail falls off. The nucleus of the sperm then joins with the nucleus of the egg. This is the zygote.
The genetic information from the mother has now joined with the genetic information from the father. The zygote then begins to divide. The cell splits into 2.
The cell then splits into 4, then 8, then 16. This process is called growth.
The cell continues to divide to form a mass of cells called the blastocyst. This implants into the wall of the uterus.

6. HUMAN REPRODUCTION Fertilisation means egg and sperm joining together.
Journey along the fallopian tube to the egg is complete. The sperm and the egg have now met.
Sperm swim up through the uterus, into the oviduct where they meet the egg.

7. HUMAN REPRODUCTION Picture of egg with sperm around it.
Picture of head of sperm entering the egg.
Picture of cell with nucleus split into two.
The genetic information from the mother has now joined with the genetic information from the father. The zygote then begins to divide. The cell splits into 2.
When the sperm enters the egg its tail falls off. The nucleus of the sperm then joins with the nucleus of the egg. This is the zygote.
Only one sperm cell can penetrate (get inside) the egg.

8. MALE REPRODUCTIVE SYSTEM
Look at the diagram of the male reproductive system and make a list of the labelled parts.

9. FEMALE REPRODUCTIVE SYSTEM
Look at the diagram of the female reproductive system and make a list of the labelled parts.

10. LOADS OF WORDS Crvx Rprdctn Tsts Vrs Sprm Gg Frtlstn Ejcltn Vgn Pns
Look at the word list below and see if you can work out what they should say. All of the vowels are missing.
Try to work out which words are to do with males and which words are to do with females.
Crvx Rprdctn
Tsts Vrs
Sprm Gg
Frtlstn Ejcltn
Vgn Pns

11. Key: Green = male, Blue= female, Purple = both.
MISSING VOWELS
Cervix.
Testes.
Ovaries.
Sperm.
Egg.
Reproduction.
Fertilisation.
Ejaculation.
Vagina.
Penis.
Key: Green = male, Blue= female, Purple = both.

12. PREGNANCY
This is the time from when a ball of cells IMPLANTS on the side of the UTERUS until the time a BABY is born 40 weeks later.
TASK
Sometimes there is more than one baby at once. For homework, research how this happens!

13. MULTIPLE BIRTH
This is the name we give to having more than one baby at once!
There are two types of twins.
Fraternal twins
Identical twins
Can you explain how this happens?
Can you explain how this happens?
Two eggs are fertilised by two different sperm and they are as different as having two pregnancies, one after the other.
One egg is fertilised and then it splits into two separate babies but they have exactly the same information.
HOW MANY DIFFERENT WAYS CAN YOU THINK OF TO HAVE TRIPLETS?
Can you find out the names for having four, five or even six babies at once?

14. THE PLACENTA Placenta is attached to the wall of the uterus
Umbilical cord
What substances go into the baby across the placenta?
What substances go from the baby across the placenta to the mother?
Food and oxygen
Carbon dioxide and waste

15. PREGNANCY
Put the following sentences into the correct order to explain what happens during pregnancy.
A After 40 weeks the baby is ready to be born.
B The ball of cells then attaches to the lining of the uterus and the cells continue to divide.
C The zygote divides and then passes down the oviduct into the uterus.
D After 12 weeks the embryo looks more like a human and is now called a foetus.
E After 4 weeks the cells have begun to specialise and the new life is called an embryo.
F The foetus is fully dependent on the mother and gets its food and oxygen through the placenta.

16. PREGNANCY The Know How! The correct order:
C The zygote divides and then passes down the oviduct into the uterus.
B The ball of cells then attaches to the lining of the uterus and the cells continue to divide.
E After 4 weeks the cells have begun to specialise and the new life is called an embryo.
D After 12 weeks the embryo looks more like a human and is now called a foetus.
F The foetus is fully dependent on the mother and gets its food and oxygen through the placenta.
A After 40 weeks the baby is ready to be born.

17. TRUE OR FALSE? Read each statement and work out
whether it is true or false:
The foetus uses its lungs to breathe oxygen.
The foetus gets oxygen and food through the mother’s blood supply across the placenta.
Smoking whilst pregnant can result in the baby receiving less oxygen from the mother’s blood.
Drinking alcohol whilst pregnant can result in the baby being born underweight or brain damaged.
The foetus eats food.
Taking drugs whilst pregnant can cause the baby’s blood vessels and heart to be damaged The baby may be small when born, premature or even still - born.

18. TRUE OR FALSE? True: False:
The foetus gets oxygen and food through the mother’s blood supply across the placenta.
Smoking whilst pregnant can result in the baby receiving less oxygen from the mother’s blood.
Drinking alcohol whilst pregnant can result in the baby being born underweight or brain damaged.
Taking drugs whilst pregnant can cause the foetus’ blood vessels and heart to be damaged and the baby may be small when born, premature or even still born.
False:
The foetus uses its lungs to breathe oxygen.
The foetus eats food.

19. BIRTH After 40 weeks the baby is ready to be born.
Amniotic fluid protects the baby. The fluid acts like a shock absorber.
Amnion splits and the amniotic fluid runs out.
The contractions continue until the placenta has passed out of the mother’s body.
During labour hormones in the mother’s body make the uterus contract.
The umbilical cord can then be cut.
The baby turns so that its head is above the cervix.
The contractions in the uterus push the baby out through the vagina.
The muscles in the cervix relax and the baby’s head passes into the vagina.

20. BABY FOOD. WHAT DO BABIES NEED?
Once the baby has left the mother it must be fed It will not get the things it needs across the placenta.
MILK is the best food for babies and babies are either fed by their mother or by special baby milk. This also provides fluid.
In the first few weeks the baby can get the antibodies it needs to fight diseases from the BREAST milk.
TASK.
Do some research about baby milk and find out what is in milk that helps babies to grow and have strong bones.

21. PUBERTY
Look at the picture below. What changes do you think happen to boys and girls when they go through puberty?

22. PUBERTY CHANGES Can you think of any more?
Fill in the following diagram with as many changes during puberty for the three sections.
Try this before you click for the answers!
Female
Both
Male
Periods start
Breasts develop
Wider hips
Body hair
Voice changes
Penis gets larger
Facial hair
Pubic hair
Body shape
Skin changes
Can you think of any more?

23. MENSTRUATION
The diagram below shows what happens during this monthly cycle.
When girls reach puberty they begin to menstruate (start their periods). This means that their body COULD have a baby.
Girls have a period once a month. The average cycle is about 28 days. 1 2 3 4 5 6 7 8 9 10 11 12 14 13 15 16 17 18 19 20 21 22 23 24 25 26 27 28
Lining of uterus sheds
Your period
Lining of uetrus begins to thicken
New egg matures
Ovulation
Egg released
- Egg travels to uterus if not fertilized, dissolves
- Lining of uterus continues to thicken
If a fertilised egg does not implant in the uterus, the wall of the uterus passes out of the vagina.
Days 1-6; this is when blood passes out of the vagina (a period).
The lining of the uterus thickens in preparation for pregnancy.
Day 14; the egg is released from the ovary. Ovulation.
The red days are the days when fertilisation could happen.

24. Which comment do you agree with? Why?
LET’S THINK!
Which comment do you agree with? Why?
Reproduction is the production of new life.
Different organisms are pregnant for different lengths of time.
Fertilisation is the production of new life and reproduction is when the male and female sex cells fuse together. Pregnancy lasts for 9 months in every organism. X

25. CHECK YOUR LEARNING 1. What are the male and female sex cells called?
2. Where is the egg usually fertilised?
3. Name 2 changes common to males and females in puberty.
4. What is the length of the average menstrual cycle?
5. What does the placenta do during pregnancy?
6. How do fraternal twins happen?
7. What is the best food for a baby?

26. CHECK YOUR LEARNING ANSWERS
1. The male and female sex cells are called the sperm and the egg.
2. The egg is usually fertilised in the fallopian ( egg) tube.
3. Body hair, skin changes.
4. 9 months.
5. The placenta takes food and oxygen to the foetus and removes carbon dioxide and waste.
6. Fraternal twins happen when two different eggs are fertilised by two different sperm.
The best food for a baby is milk as it has everything in it that a baby needs.