Contains muslces that allow it to control
the diameter of the Pupil and therefore
how much light enters the eye.
Sclera
Though supporting wall of
the Eye.
Cornea
Transpartent outer layer found at the front of
the Eye. It refracts and bends the light into
the Eye.
Lens
Focuses the light onto the
Retina (which contains
receptors which are sensitive to
light intensity and colour).
Optic Nerve
Carries impulses from
receptors on the Retina to
the Brain
Ciliary Muscles
Circular ring of muscle that
surrounds the Lens adjusting
the diameter of the Lens.
Suspensory
Ligaments
Connects the Cilary Body
with the Lens keeping it in
place.
Pupil
The black hole in the centre of
the Eye.
Retina
Contains 2 main types of light receptors
which can produce colour vision.
The Iris Reflex
For a bright light it gets detected by the eye and
that triggers a relfex which makes the pupil
smaller. The Cirluary Muscles in the Iris contract
and the Radial Muscles Relax reducing the
amount fo light entering the Eye.
The opposite to the bright light occurs
for a dim light but instead the Radial
Muslces contract and the Circular
Muscles relax making the Pupil wider.
Focusing on Near and Far
objects
Near objects
The Ciliary Muscles contract which
slackens the Suspensory Ligaments. This
makes the Lens go fatter increasing the
amount of refracted light.
Far objects
The Ciliary Muscles relax which allows the
Suspensory Ligaments to pull tight. This
makes the Lens go thinner making it refract
light by a smaller amount.