eyes Flashcards
what is the eyelid?
fold of skin covering eye, cleans and protects
what is the cornea?
transparent eye covering, protects and helps converge light rays
what is the sclera?
white part, made of tough collages fibres. provides protection and support
what is the retina?
layer of photoreceptors at back of eye, detects light rays focused by cornea and lens
what is the choroid?
layer of blood vessels with black a pigment. nourishes eye and absorbs light
what is the iris?
coloured ring of muscles around pupil, controls amount of entering light
what is the pupil?
hole in middle of iris, allows light to enter eye
what is the lens?
transparent, flexible and can change shape due to ciliary muscles. focuses light onto retina and focusing on objects
what is the ciliary body?
attached to underside of lens, produces aqueous humour and alters lens shape helping focus
what is vitreous humour?
behind the lens, gives eyeball shape
what is aqueous humour?
found behind cornea, helps keep rounded shape provides nutrients to cornea and lens
what are the lateral rectus muscles?
on lateral side of eye, help orient pupil away from body centre
what is the medial rectus muscle?
on medial side of eye, help orient pupil towards body centre
what is the fovea?
spot located in macula, which has high cone cell density. gives sharp central vision and light is focused onto this spot by lens
what is the optic disc?
blind spot, no photoreceptors. optic nerves leave the eye here
