B5 The eye

Question 1

What is the function of the cornea?

Answer 1

Refracts light- bends as it enters the eye

Question 2

What is the function of the iris?

Answer 2

Controls how much light enters the pupil

Question 3

What is the function of the lens?

Answer 3

Further refracts light to focus it on the retina

Question 4

What is the function of the retina?

Answer 4

Contains the light receptors

Question 5

What is the function of the optic nerve?

Answer 5

Carries impulses between the eye and the brain

Question 6

What is the function of the sclera?

Answer 6

Tough white outer layer of the eye. It helps protect the eye from injury

Question 7

What are the 2 main light receptors in the retina?

Answer 7

Rods and cones

Question 8

Which light receptor is more sensitive to the light therefore making it more useful in dim light?

Answer 8

rods

Question 9

What does the reflex action control?

Answer 9

The amount of light entering the eye

Question 10

What is the reflex action?

Answer 10

Automatic and rapid response to a stimulus

Question 11

To focus on a near object does the lens become thicker or thinner?

Answer 11

Thicker this allows the light rays to refract more strongly

Question 12

To focus on a far object does the lens become thicker or thinner?

Answer 12

thinner this allows the light rays to refract slightly