The Eye Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

Go revise a diagram

A

NOW

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How does the eye focus?

A

The cornea and the lens converge light rays from objects and focus them to the retina

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is accommodation?

A

The focusing of the eye

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What happens during DISTANT accomodation?

A

Ciliary muscles relax
Lens pulled thin/tight/flat
Suspensory ligament taut (pulls out lens)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What happens during NEAR accomodation?

A

Ciliary muscles contract
Lens becomes rounded/fat
Suspensory ligament loose/relaxed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What two sorts of receptor cell does the retina contain?

A

Rods and Cones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Rods and Cones are examples of

A

Receptor cells in the retina

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Rods are

A

Sensitive to quite dim light, they only let you see in black and white

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Cones…

A

give colour vision, but only in bright light

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How is an image obtained in the brain?

A
  1. Light falls onto receptor cells in the retina and a message is sent along the optic nerve to the brain
  2. The brain sorts out the messages and makes an image
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Where are the receptor cells packed closely?

A

In the fovea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What does the cornea do?

A

Bends and refracts most of the light rays so that they are focused on the retina

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What happens to light rays of a nearby object?

-Use finger as an example?

A

They are bent inwards a lot

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What happens to light rays of a far object?

A

Since the rays are almost parallel, they will not bend a lot

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How much does a fat/thin lens bend the light

A

A fat lens will bend light more

A thin lens will bend light less

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What causes long sighted eyes?

A

Weak lenses, when the light cannot be bent enough (thin lenses) to focus on the retina and end us focusing behind it

17
Q

What causes short sighted eyes?

A

When the light rays are bent too much (fat lenses) so that it ends up focusing too far in front of the retina

18
Q

Correction for long sight?

A

Wearing convexed lenses

19
Q

Correction for short sight?

A

Wearing concaved lenses