The Eye

Question 1

What does it mean when your pupil constricts?

Answer 1

It means that it shrinks, most probably due to bright light.

Question 2

What does it mean when your pupil dilates?

Answer 2

It means that it gets bigger, most probably because there is not much light.

Question 3

What does the cornea do?

Answer 3

The cornea focuses light onto the retina. It is clear, colourless, and curved.

Question 4

What does the lens do?

Answer 4

The lens fine-tunes the focusing of the light onto the retina. It is clear, colourless and curved and can change shape.

Question 5

What does the retina do?

Answer 5

The retina detects light waves and produces impulses. It contains rod cells, cone cells, and sensory neurones.

Question 6

What does the iris do?

Answer 6

The iris controls the pupil size. It contains muscles.

Question 7

What is the scientific term for short-sightedness?

Answer 7

Myopia

Question 8

What is the scientific term for long-sightedness?

Answer 8

Hyperopia

Question 9

Short-sightedness is when…..

Answer 9

…..distant objects are blurry

Question 10

Long-sightedness is when………

Answer 10

……close objects are too blurry.

Question 11

What is one way of correcting short-sightedness?

Answer 11

Using laser surgery to reshape the cornea

Question 12

What is one way of correcting long-sightedness

Answer 12

Using converging lenses.

Question 13

The cells in the retina that cause color blindness are…..

Answer 13

…..cones

Question 14

What is the eye problem that can be fixed by replacing the lens?

Answer 14

Cataracts

Question 15

What muscles operate the lens?

Answer 15

Ciliary Muscles

Question 16

What cells detect low levels of light?

Answer 16

Rods

Question 17

What causes the pupil to constrict and dilate?

Answer 17

Iris Muscles

Question 18

What is the correct order of parts of the eye when light hits them: retina, cornea, pupil, lens?

Answer 18

1. Cornea
2. Pupil
3. Lens
4. Retina

Question 19

Can colour-blindness be fixed with surgery?

Answer 19

No

Question 20

What do rod cells do?

Answer 20

Rod cells detect low levels of light

Question 21

What do cone cells do?

Answer 21

Cone cells detect colours in bright light

Question 22

The lens is made thinner and fatter by…..

Answer 22

…..ciliary muscles.

Question 23

How must the lens be for short distance?

Answer 23

Wide and short

Question 24

How must the lens be for long distances?

Answer 24

Long and narrow.

Question 25

For short-sightedness, what sort of lens should you use?

Answer 25

For Myopia, Use a concave lens
The lens should look like this: )(

Question 26

For long-sightedness, what sort of lens should you use?

Answer 26

For Hyperopia, Use a convex lens
The lens should look like this: ()