Page 35 - Future Stars Science Explorer-5

surroundings. We are able to see, hear, smell, taste, and feel through them.
The five sense organs in our body are the eyes, ears, nose, tongue and skin.

Eyes

Sclera
The eyes consist of eye balls that fit into Cornea
sockets in the skull. The eye balls are Iris
protected by eyelids and eyelashes,

that keep them clear and dust free. Lens Optic
nerves
Aqueous
The eye ball has the following three humor Retina

main layers : Internal structure of a human eye

Cornea : It is the outer transparent layer covering the visible part of the eye.

Pupil Sclera : It is the white part of the eye. In
the centre of the eye lies the round iris.

The iris is coloured, it can be blue,
black, green, brown, etc. In the centre of

Pupil enlarged in Pupil dialated in the iris lies a black spot or hole called the
dim light bright light pupil. The pupil controls the amount of
light that enters the eye. In very bright light, the pupil contracts or becomes

smaller in order to keep away extra light. In dim light, the pupil enlarges, in
order to take in more light.

Retina : It is the innermost layer of the eye. It acts like a screen on which the
image of the object we see is formed. Messages from the retina are sent to the
brain through the optic nerves.

Ears

Inner ear
Our ears help us to hear sounds and also Ear canal
maintain balance. The outer ear helps us

to receive and direct sound waves to the Auditory
inner ear. nerves

Each ear has three parts : the outer ear, Eustachian
tube
the middle ear and the inner ear. The Pinna Middle ear

outer ear catches the sound and sends Eardrum
Internal structure of an ear

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