1. natural
sciences 4

2. Can you name the parts of the digestive system?
Esophagus
Food goes down this tube to the stomach.
Mouth
Food is broken up by the teeth and mixed with saliva by the tongue.
Small intestine
There are lots of blood vessels. Nutrients pass into the blood.
Stomach
Gastric juices make the food into a thick liquid.
Large intestine
The waste passes through. Water goes out into the body and the waste becomes harder.
Anus
The waste, called faeces, leaves the body.

3. Can you label the parts of the digestive system?
Kidneys
When the blood goes through here, excess water and waste products are dropped off and made into urine.
Ureters
The urine goes down these tubes to the bladder.
Bladder
The urine is stored here. When it is full it sends a message to our brain.
Urethra
The urine leaves the body through this tube.

4. What’s the difference between veins and arteries?
They return the blood (with waste) back to the heart.
Arteries
They carry blood (with oxygen) from the heart to the rest of our bodies.
What do you think the one-way valves are for?
They prevent the blood from going in the opposite direction!

5. Do you know where does oxygen pass to and from the blood?
At the alveoli, through the capillaries!

6. Can you order this sequence?3 1 2

7. What happened to the cat?
Its nervous and locomotor systems were in action!
1. He saw a dog.
2. Its eyes sent a message to its brain.
3. Its brain sent an order to its locomotor system.
4. It ran away!

8. From egg to baby 1
An egg is fertilised by a sperm.

9. From egg to baby 2
The egg divides again and again and becomes attached to the wall of the uterus.

10. From egg to baby
An embryo develops. At six weeks old it is about the size of a small seed. Nutrients and oxygen travel from the mother to the embryo along the umbilical cord. 3

11. From egg to baby 4
The embryo becomes a fetus at nine weeks. It’s about the size of an olive. It has arms and legs and it starts to have a face.

12. From egg to baby 5
At three months it has all its organs. It’s about the size of an avocado.

13. From egg to baby 6
At nine months it is ready to be born… is it a boy or a girl?

14. From egg to baby 7
The baby moves headfirst down the vagina and comes out into the world. It is born. The umbilical cord is cut and becomes the belly button and the baby breathes on its own and gets nutrients from its mother’s milk.

15. ovaries uterus fallopian tubes vagina
Can you label the female reproductive system?
ovaries
uterus
fallopian tubes
vagina

16. Can you label the male reproductive system?
testicles
urethra
penis