Structure of the eye

Question 1

what happens to the eye in bright light?

Answer 1

• the iris becomes wider
• circular muscles contract
• radial muscles relaxes
• pupil becomes smaller

Question 2

what happens in dim light?

Answer 2

• the iris become narrower
• circular muscles relax
• radial muscles contract
• pupil becomes wider

Question 3

where are the muscles in the eye?

Answer 3

the iris

Question 4

how does the eye focus on distant objects?

Answer 4

• ciliary muscles relax
• suspensory ligaments pull tightly
• makes the lens long and thin
• light bends a little bit
• focuses on the retina

Question 5

how does the eye focus on close objects?

Answer 5

• ciliary muscles contract
• suspensory ligaments slacken
• makes the lens short and fat (rounded)
• light bends quite a lot
• focuses on the retina

Question 6

function of the conjunctiva?

Answer 6

lubricates and protected the surface of the eye

Question 7

function of the cornea?

Answer 7

refractes light into the eye

Question 8

function of the iris?

Answer 8

controls the diameter of the pupil

Question 9

function of the lens?

Answer 9

focuses the light onto the retina

Question 10

function of the retina?

Answer 10

detects then light

Question 11

function of the optic nerve?

Answer 11

carries impulses from the receptor to the brain

Question 12

name the 2 light receptors found in the eye? which one is sensitive to colour?

Answer 12

rod and cone, cone is sensitive to colour

Question 13

how does the cornea receive oxygen when it has no blood vessels?

Answer 13

oxygen diffuses in from the outer surface

Question 14

what is fovea?

Answer 14

good colour vision