Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

BRS Year 2 > Anatomy of the Visual System > Flashcards

Anatomy of the Visual System Flashcards

1
Q

How many types of tears are there? What are they called?

A

3 types
Basal
Emotional
Reflex

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

What are the afferent components of the lacrimal system?

A

Cornea, cranial nerve V1 (ophthalmic division of trigeminal) supplies it

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

What are the efferent components of the lacrimal system?

A

Parasympathetic

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

What neurotransmitter is involved with the lacrimal system?

A

Acetylcholine

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

What produces tears?

A

Lacrimal gland

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

What do tears drain through?

A

The 2 puncta, these are the opening on the medial lid margin, they then flow through superior and inferior canaliculi

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

Where do tears gather and then exit?

A

Gather the tear sac amd then exit through tear duct into nasal cavity

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

What is the role of the tear film? (4)

A

Maintain a smooth cornea to air surface
Provide oxygen supply to the cornea
Allow removal of debris alongside blinking
Bactericide

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

What is the blood supply to the cornea?

A

There is no blood supply to the cornea

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

How may layers are there to the tear film? What are they called?

A 
3 layers (from superficial to deep they are):
Lipid layer (reduces tear evaporation- oil produced by row of meibomian glands along lid margins)
Water layer (aqueous tear film)
Mucin layer (maintains surface wetting)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the conjunctiva?

A

A thin, transparent tissue that covers the outer surface of the eye
Starts at the cornea and lines inside of the eyelid

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

What is the blood supply to the conjunctiva?

A

Supplied by tiny blood vessels that we can’t see

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

How many layers are there in the coat of the eye? What are they called?

A

3 layers (from outer to innermost they are):
Sclera- hard and opaque
Choroid- pigmented and vascular
Retina- has neurosensory tissue

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

What is the sclera?

A

‘White of the eye’
Tough, opaque tissue that serves as eyes protective outer coat
High water content

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

How many layers does the cornea have? What are they called?

A 
5 layers:
Epithelium (outermost)
Bowman's membrane
Stroma
Descement's membrane
Endothelium
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the cornea?

A

The transparent dome shaped window covering the front of the eye

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Describe the water content of the cornea

A

Low

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the role of the cornea?

A

It is a powerful refracting surface (2/3 of the eyes refracting power)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the significance of the endothelium of the cornea?

A

It pumps fluid out of the cornea and prevents corneal oedema

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the uvea?

A

It is the vascular coat of the eyeball

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What does the uvea lie between?

A

The sclera and the choroid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

How many layers are there in the uvea? What are they called?

A

3 layers
Iris
Ciliary body
Choroid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Describe the role of the iris

A

It controls how much light is let into the eye, and has an opening in the middle which is the pupil. Muscles allow the pupil to constrict and relax

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is the choroid composed of?

A

Tiny blood vessels that nourish the eye

25
Q

What is the role of the lens?

A

To allow transparency

Has refractive power also (1/3 of the eye)

26
Q

Describe the structure of the lens

A

Outer acellular capsule

Inner elongated cell fibres

27
Q

What is it called when lens transparency is lost with age?

A

Cataract

28
Q

Describe the retina and where its found

A

It is a very thin layer of tissue that lines the back of the eye

29
Q

What is the role of the retina?

A

To capture light rays that enter the eye

30
Q

What happens to light rays that are captured by the retina?

A

They are sent to the brain for processing via the optic nerve

31
Q

What is the optic disc?

A

The visible part of the optic nerve that connects to the retina

32
Q

Where does the optic nerve connect to the eye?

A

At the back near the macula

33
Q

What is formed where the optic nerve meets the retina?

A

A blind spot, there are no sensitive light cells here

34
Q

How many layers are there to the retina? What are they called and what are their roles?

A

3 layers
Outer layer: photoreceptors, 1st order neurons, detect light
Middle layer: Bipolar cells, 2nd order neurons, local signal processing to improve contrast sensitivity
Inner layer: retinal ganglion cells, 3rd order neurons, transmits signals from eye to brain

35
Q

What type of cell is found in the outer layer of the retina?

A

Photoreceptors

36
Q

What type of cell is found in the middle layer of the retina?

A

Bipolar cells

37
Q

What type of cell is found in the inner layer of the retina?

A

Retinal ganglion cells

38
Q

What is the macula?

A

A small highly sensitive part of the retina that is responsible for detailed central vision and allows us to appreciate detail for tasks such as reading

39
Q

What is the fovea?

A

The centre of the macula, the most sensitive part of the retina

40
Q

What type of cells are found in the fovea?

A

Highest conc of cones (allows perception of detail) and lowest conc of rods

41
Q

What does central vision include?

A

Detailed vision during the day
Colour vision
Reading
Facial recognition

42
Q

How is central vision assessed?

A

Visual acuity assessment

43
Q

What does peripheral vision include?

A

Shape, movement, night vision, navigation vision

44
Q

How is peripheral vision assessed?

A

Visual field assessment

45
Q

What happens if there is a loss of visual field?

A

This is an impairment in peripheral vision and so people cannot navigate
May need a stick even with perfect visual acuity

46
Q

What are photoreceptors for?

A

Visual processing

47
Q

What are the 2 types of photoreceptors?

A

Rods and cones

48
Q

Describe rods

A

They have a long outer segment which is photo-sensitive
They have a slow response to light but are 100x more sensitive to light than cones
They are responsible for night vision
120 million rods

49
Q

What is the scientific name for night vision?

A

Scotopic vision

50
Q

Out of rods and cones which is more sensitive to light?

A

Rods

51
Q

Describe cones

A

Less sensitive to light but fast response to light
Responsible for day vision and colour vision
6 million cones

52
Q

What is the scientific name for day vision?

A

Photopic vision

53
Q

How does the eye see colour?

A

Through different photoreceptors
S cones= blue
M cones= green
L cones= red

54
Q

What colours are rods sensitive to?

A

No colours

55
Q

What is deuteranomaly?

A

Aka daltonism

Partial colour blindness (the most common form) where they don’t perceive red

56
Q

What do we call full colour blindness?

A

achromatopsia

57
Q

What test is used to diagnose colour blindness?

A

Ishihara test

58
Q

What is the function of the lens?

A 
Transparency 
Regular structure
Refractive power
1/3 of eye focusing power-  higher refractive index that aqueous fluid and vitreous
Accommodation
Elasticity

BRS Year 2 (110 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions