lesson 4 the eye

Question 1

the eye is what

Answer 1

a sense organ

Question 2

the eye contains what

Answer 2

receptors sensitive to both light intensity and also the colour of light

Question 3

light rays pass through where

and what is it called

Answer 3

the transparent front of the eye

called the cornea

Question 4

what is the job of the cornea

Answer 4

to start the focussing of light rays

Question 5

the light rays then pass through where

Answer 5

the pupil, in the centre of the iris

Question 6

what is the iris

Answer 6

the coloured part of the eye

Question 7

the light rays (after the pupil) then pass through where

Answer 7

the lens

Question 8

what is the job of the lens

Answer 8

to focus the light rays onto the back of the eye

Question 9

one key feature of the lens is what

Answer 9

it can change its shape which allows us to focus on distant or near objects

Question 10

when the lens can change its shape which allows us to focus on distant or near objects, this is called what

Answer 10

accommodation

Question 11

after the light rays are now focused where (after the lens)

Answer 11

at the back of the eye which is called the retina

Question 12

what does the retina contain

Answer 12

receptor cells for light

Question 13

the receptor cells in the retina allow us to detect what

Answer 13

light intensity and light colour

Question 14

the receptor cells in the retina, then send what

Answer 14

electrical impulses down the optic nerve to the brain

Question 15

the white part of the eye is called what

Answer 15

the sclera

Question 16

the sclera’s tough outer structure does what

Answer 16

protects the eye

Question 17

what works with the lens

Answer 17

ciliary muscle
suspensory ligaments

Question 18

together the ciliary muscle and suspensory ligaments allow us to do what

Answer 18

focus on distant or near objects

Question 19

what is the pupil

Answer 19

the space in the centre of the iris, where the light passes through

Question 20

if you are in a dark room, the amount of light entering the eye is now low, meaning what

Answer 20

the drop in light intensity is sensed by light receptors in the retina and these send electrical impulses to the brain

Question 21

the brain then does what (dark room)

Answer 21

sends electrical impulses to specific muscles in the iris

Question 22

the brain sends electrical impulses to specific muscles in the iris, then what (dark room)

Answer 22

the muscles contract, causing the pupil to become larger, this now allows more light to enter the eye

Question 23

in a dark room eye scenario is it a reflex action

Answer 23

no as it does not involve the brain

Question 24

in a bright room what effect would there be from the dark room

Answer 24

an opposite effect as the reflex causes the pupil to become smaller

Question 25

the reflex causing the pupil to become smaller reduces what

(opposite from dark room effect)

Answer 25

the amount of light entering the eye and protects it from damage