The Eye Flashcards
Cornea
Transparent lens that refracts light as it enters the eye
Iris
Controls how much light enters the pupil
Lens
Transparent disc that can change shape to focus light onto the retina
Retina
Contains light receptor cells - rods (detect light intensity) and cones (detect colour)
Optic nerve
Sensory neurone that carries impulses between the eye and the brain
Pupil
Hole that allows light to enter the eye
Ciliary muscles
A ring of muscle that contracts and relaxes to change the shape of the lens
Suspensory ligaments
Ligaments that connect the ciliary muscle to the lens
Sclera
Strong outer wall of the eyeball that helps to keep the eye in shape and provides a place of attachment for the muscles that move the eye
Fovea
Region of the retina with the highest density of cones (colour detecting cells) where the eye sees particularly good detail
Aqueous humour
Watery liquid between the cornea and the lens
Vitreous humour
Jelly-like liquid filling the eyeball
Choroid
Pigmented layer of tissue lining the inside of the sclera that prevents the reflection of light rays inside the eyeball
Blind spot
The point at which the optic nerve leaves the eye, where there are no receptor cells
What happens when an object is close up
- the ciliary muscles contract
- this causes the Suspensory ligaments to loosen
- this stops the Suspensory ligaments from pulling on the lens, which allows the lens to become fatter
- light is refracted more
