The Eye and Muscle
Conjunctiva Protects Cornea
Sclera Protects against damage, site
of attachment of eye muscles
Cornea Most refraction occurs here
Aqueous Humour Maintains shape at the front
of the eye
Iris Adjusts size of pupil to
control the amount of light
entering
Pupil Area through which light
enters lens
Ciliary body Adjusts shape of lens to focus
light rays
Suspensory Ligaments Transfers tension in the wall
of the eyeball to make lens
thinner
Lens Refracts light
Vitreous Humour Maintains shape of the rear
part of the eye
Retina Rods and cones
Fovea Gives clearest daylight colour
vision
Choroid Prevents reflection of light
back through the eye and
contains blood vessels to
supply retina
Optic nerve Transmits impulses from the
retina to the brain
Blind spot No light sensitive cells
Rod cells
-Rhodopsin, opsin and retinal
-When stimulated by light it breaks down into these components, creating a generator potential, can
cause sufficient depolarisation that can then cause an action potential
Conjunctiva Protects Cornea
Sclera Protects against damage, site
of attachment of eye muscles
Cornea Most refraction occurs here
Aqueous Humour Maintains shape at the front
of the eye
Iris Adjusts size of pupil to
control the amount of light
entering
Pupil Area through which light
enters lens
Ciliary body Adjusts shape of lens to focus
light rays
Suspensory Ligaments Transfers tension in the wall
of the eyeball to make lens
thinner
Lens Refracts light
Vitreous Humour Maintains shape of the rear
part of the eye
Retina Rods and cones
Fovea Gives clearest daylight colour
vision
Choroid Prevents reflection of light
back through the eye and
contains blood vessels to
supply retina
Optic nerve Transmits impulses from the
retina to the brain
Blind spot No light sensitive cells
Rod cells
-Rhodopsin, opsin and retinal
-When stimulated by light it breaks down into these components, creating a generator potential, can
cause sufficient depolarisation that can then cause an action potential
