THE DIGESTIVE SYSTEM 3r

THE DIGESTIVE SYSTEM 3r

The digestive system is a group of organs that work together to help us digest food.

+ We take in food through our mouth.

+ It passes down into our stomach and intestine.

+ The intestine separates the nutrients from the waste and expels the waste from our body.

+ The nutrients are passed to the circulatory system, where they move around the body.

THE RESPIRATORY SYSTEM 3r

THE RESPIRATORY SYSTEM 3r

The respiratory system is a group of organs that work together to help us breathe.

+ We breathe in air through our nose and mouth.

+ The air goes down into our lungs.

+ Oxygen is passed to the circulatory system, where it moves around the body.

+ We breathe in oxygen and breathe out carbon dioxide.

How our eyes and ears work

How our eyes and ears work

Our brain is the control centre of our body. It reads signals from our eyes and ears and tell us what we can see and hear.

How do we see things?

1. Light reflects off an object and enters the eye through the pupil.

2. The light goes through the lens and makes an image on the retina at the back of the eye. The image is upside down.

3. The retina sends the information to the brain.

4. The brain reads the signals and tells us what we can see.

How do we hear things?

1. Sound waves enter through the outer ear.

2. The waves hit the eardrum in the middle ear and make it vibrate.

3. This makes the liquid in the inner ear move and send signals to the brain.

4. The brain reads the signals and tells us what we can hear.

HEARING

HEARING

Our ears are the organs of hearing. We can hear loud souns and quiet sounds.

Our ears have three parts: the outer ear, the middle ear and the inner ear.

Our ears are very delicate. Earwax is a sticky substance inside our ear canal. It protects our ear from dirt and infection.

 

THE CIRCULATORY SYSTEM

THE CIRCULATORY SYSTEM

The circulatory system consists of the heart, blood vessels and blood. It moves blood through the heart and around the body. Blood gives our cells the oxygen and nutrients they need. Blood also collects waste products, such carbon dioxide, and takes them to the parts of the body which expel them.

SIGHT

SIGHT

Our eyes are the organs of sight. We can see different shapes and colours.

The pupils are black but the iris can be different colours.

Our eyes are very delicate and protected by the eyebrows, eyelashes and eyelids. These stop sweat and dust getting into our eyes.