The eye Flashcards

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

cornea

A

completely transparent
no blood vessels
refracts light (always by the same amount)
first structure light meets

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

pupil

A

not a structure
gap in middle of iris

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

iris

A

colour of eye
determines size of pupil
made up of circular and radial muscles

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

lens

A

refract light
can change shape
-changes depending on how strongly light needs to be refracted
- so light is refracted to hit retina

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

retina

A

made of two diff receptor cells
cone cells
rod cells

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

cone cells

A

sensitive to colour of light
allow us to see in colour
dont work well in low light conditions

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

rod cells

A

more sensitive to light
only allow us to see in black and white

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

fovea

A

spot on retina that only has cone cells
spot we try to focus light on to see most clearly

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

optic nerve

A

takes all impulses generated by receptor cells and transmits them to the brain

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

making pupil smaller

A

circular muscles contract
- squeezing pupil smaller
radial muscles relax
- so they can be stretched over a larger space

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

making pupil larger

A

circular muscles relax
radial muscles contract
- make them shorter
- pulling pupil open

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

pupil in bright light

A

can be damaging to retina
pupil gets smaller to allow less light in

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

pupil in low light

A

gets larger
allows more light in
allows us to see in dark

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

accommodation

A

reflex that changes refractive power of lens

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

looking at nearby objects

A

ciliary muscle contracts
- inwwards towards lens
- suspensory ligaments slacken
- no longer pulling on lens so it can return to its
natural, fatter shape
- light is refracted more strongly

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

distant objects

A

light doesnt need to be refracted as strongly
lens need to be stretched out, less curved
- cornea has already mostly refracted the light
- reduces refracting power
-ciliary muscle relaxes, moving away from lens
- pulls suspensory ligaments taut
- stretches out lens