unit 1 science 3rd: the human body

UNIT 1: The

Human Body

PART I: Hearing and Sight

SIGHT

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

• The pupil is black but the iris can be of different colours.

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

w

EyelidEyelash

esPupilIris

External Parts of the Eye

Sweat

Dust

Do you remember?

??

? ??

Internal Parts of the Eye

How do we see things?

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

Light

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

upside down.

Retina

Upside down

The retina sends the information to the brain.

Retina

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

What colour are the pupils?a) Brownb) Blue or greenc)Black

c) Black

What colour are the iris?a) Different coloursb) Blue or greenc)Black

• A) Different colours

HEARING

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

Our ears have three parts:

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

ears from infection.

Earwax

What we see

How do we hear things?

Are these ears different from ours?

Rabbits and other animals have larger ears to capture better sounds.

Why have we got two ears?

• Some ear slices are from: http://www.slideshare.net/Marigallardocapiscol/cienceunit-1-el-cuerpo-humano-espaol