Whats the eye action when there is bright light?

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• The radial muscles of the iris relax.
• The circular muscles contract.
• The pupil gets smaller.
• Less light enters the eye.
• The delicate retina is protected from damage.

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• The radial muscles of the iris contract.
• The circular muscles of the iris relax.
• The pupil gets bigger.
• More light enters the eye.
• It's easier to form an image when there's not much light around.

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Seeing Nearby objects:

• The ciliary muscles contract.
• The lens become rounded and fatter.
• The ciliary body becomes a smaller circle.
• The suspensory ligaments slacken.
• Light refracts more.

Seeing Distant objects:

• The ciliary muscles relax.
• The ciliary body becomes a larger circle.
• The suspensory ligaments pull on the lens.
• The lens is stretched into its thin shape.
• Light refracts less.

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• Retina: contains light receptor cells.
• Cornea: light refracts through this.
• Optic nerve: it has sensory neurones that carry nervous impulses to the brain.
• Lens: it refracts the light passing through it.
• Scelera: is the tough outer surface of the eyeball.
• Iris: made of muscles that control the size of the pupil.
• Pupil: light passes through this hole into the eye.
• Suspensory ligaments: these holds the lens in its position and either contract or relax in the right occasion.
• Ciliary muscle: it contracts when looking at near objects and it relaxes when looking at distant objects.