Homeostasis - the eye

Question 1

what is the eye?

Answer 1

it is a sense organ that contains receptors sensitive to light intensity and colour of light

Question 2

how does the eye detect light?

Answer 2

1. light rays pass through transparent front of the eye the cornea which focus the light rays
2. then pass through pupil in middle of the iris. iris is coloured part of eye
3. now through the lens which focus light on back of the eye, the retina.
4. retina contains receptors sensitive to cells for light, allowing us to detect light intensity and colour
5. receptors now send electrical impulses down optic nerve to brain

Question 3

what is accommodation?

Answer 3

where the lens can change its shape allowing us to detect light intensity and colour

Question 4

what is the sclera?

Answer 4

the thought outer structure that protects the eye

Question 5

how does the lens focus on near and distant objects?

Answer 5

the ciliary muscles and suspension ligaments work with the lens to let it change shape

Question 6

what is the pupil?

Answer 6

the space in the centre of the iris that light rays pass through

Question 7

what does the iris control?

Answer 7

size of pupil

Question 8

what happens to our eyes when we go into a dark room?

Answer 8

the drop in light intensity is sensed by the light receptors in retina and sends electrical impulses to the brain.brain sends electrical impulses to specific muscles in the iris to contract changing pupil to get larger and for more light to enter the eye. this is a reflex act.

Question 9

what happens to the pupil when light intensity is brighter?

Answer 9

it will get smaller to let less light through the eye to protect it from damage