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(HS) Optics 8 > Human Vision > Flashcards

Flashcards in Human Vision Deck (13)
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1
Q

What does the cornea do?

A

Light rays are refracted by the cornea which helps to force the light on the retina.
The cornea does most of the focusing of the light rays.

2
Q

What is the iris and what does it do?

A

The iris is the colored part of the eye. It controls the size of the pupil and regulates the amount of light that enters the eye.

3
Q

What is the pupil?

A

A hole in the iris that light passes through to reach the retina

4
Q

What is the sclera?

A

The tough cover of the eyeball that forms the white part of the eye

5
Q

What does the lens do?

A

Refines the refraction to further focus the light.

The lens gets thicker and thinner depending on the distance of the object.

6
Q

What do the ciliary muscles do?

A

Controls the thickness of the lens.

When muscles contract, the lens becomes thicker and focuses nearby objects.

7
Q

What is the retina?

A

The area where the image is produced and converted into nerve signals.

8
Q

What does the optic nerve do?

A

Carries the nerve signals to the brain

9
Q

How is an image produced?

A

The image is produced in the retina and the image is upside-down

10
Q

What are the 2 types of light receptor cells?

A

Rods and cones

11
Q

What are rods?

A

Help you see black and white.

There are 120 million per eye.

12
Q

What are cones?

A

Help you see colors.
They have 3 kinds of cells each processing red, green or blue.
There are 6 million per eye.

13
Q

What is the blind spot?

A

The area where the optic nerve enters the retina and does not have any light-sensing cells.