Download - Unit 2.the senses
The senses
We use our senses and our nervous system to interact with the world.
We have five senses
sight
hearingsmell
taste
touch
We use our senses and our nervous system to interact with the world.
We have five senses
sight
hearingsmell
taste
touch
Each of these senses sends a message through the nervous system to our brain
So we know what is happening around us and can respond.
Our eyes are the organs of sight.
We can see different shapes, sizes and colours.
Match
Our eyes are very delicate
and are protected by our…eyebrows,eyelashesand eyelids.
These stop sweat and dust getting into our eyes.
The iris is a big coloured circle at the front of the eye. The pupil is a black circle in the middle of the iris.
Light enters the eye through the pupil and it makes an image on the retina at the back of the eye. The retina sends this information to our brain and this is what we see.
pupil
retina
Our ears are the organs of hearing.
We can hear sounds that are loud and sounds that are quiet.
Match
Three small bones
eardrum
cochlea
Our ears have three parts:1.The outer ear is the part of our ear that is visible.2. In the middle ear there are three small bones and the eardrum.
3. The cochlea is in the inner ear.
Look at this video.
Sounds enter the outer ear and go into the middle ear. The eardrum vibrates. These vibrations travel along the three small bones to the cochlea. In the cochlea, the vibrations are turned into signal. Nerves carry signals to our brain, and this is what we hear.
Our nose is the organ of smell.
We can identify
good and bad smells.
Air enters the nose through two holes called the nostrils.
This air goes to the olfactory nerve. The olfactory nerve detects smells in the air and sends this information to our brain. This is what we smell.
The tongue is the organ of taste.
We can identify different tastes: swee
tsalty
bitter
and
sour
Match
These taste buds identify different tastes. Nerves send
the information about the different
tastes to brain.
Our tongue is covered in many taste buds.
We can identify four different tastes:
Our skin is the organ of touch.
We can feel things that are hot or cold, soft or hard
and rough or smooth
Our body is covered in skin.
The skin on our fingertips is very sensitive.
Nerves send the information from the skin to our brain.
The nervous systemThe nervous system
controls everything we do: thinking, walking, talking, sleeping, eating and even breathing! The most important part of the nervous system is our brain. The brain is an organ inside our head.It sends and receives information to different parts of our body through the nerves. We have nerves all over our body.