Vision

Question 1

What is the outside side of the eye called?

Answer 1

Temporal

Question 2

What is the inside side of the eye called?

Answer 2

Nasal

Question 3

Which side does the optic nerve go off to?

Answer 3

Nasal

Question 4

What is the sclera?

Answer 4

Non-stretchy white part of the eye

Question 5

What is the function of the sclera?

Answer 5

Anchoring point for the muscles that move the eye

Question 6

What is the cornea?

Answer 6

Transparent bit at the front of the eye

Question 7

What is the function of the cornea?

Answer 7

Bends light rays with the lens

Question 8

What is the pressure within the eye generated by?

Answer 8

Aqueous humour

Question 9

What is the aqueous humour in the eye generated and reabsorbed by?

Answer 9

Generated by the ciliary body and reabsorbed through the angle of the eye

Question 10

What do you have behind the lens?

Answer 10

Vitreous humour

Question 11

What is vitreous humour?

Answer 11

Jelly - like substance

Question 12

What is the iris?

Answer 12

Ring of muscle

Question 13

What happens in the eye to adjust for close vision?

Answer 13

Ciliary body contracts = smaller = thicker lens

Question 14

What controls how much light enters the eye?

Answer 14

Iris

Question 15

What is the function of the retinal pigment epithelium?

Answer 15

Provides biochemical support for the photoreceptors, holds the retina in place and prevents it from peeling away

Question 16

What does the neural retina contain?

Answer 16

Photoreceptors and retinal ganglion cells

Question 17

What do retinal ganglion cells form?

Answer 17

The optic nerve

Question 18

Where do retinal ganglion cells run?

Answer 18

Across the surface of the retina

Question 19

Which side of the brain do the nerves that come from the nasal bit of the retina go to?

Answer 19

Opposite sides

Question 20

Which side of the brain do the nerves that come from the temporal bit of the retina go to?

Answer 20

Stay on the same side

Question 21

Where do the retinal nerves project to?

Answer 21

The lateral geniculate nucleus

Question 22

What are rods useful for?

Answer 22

Night vision

Question 23

What are cones useful for?

Answer 23

Day vision

Question 24

What are the bits of the cone?

Answer 24

Inner segment, axon, synaptic terminal and outer segment

Question 25

What is in the inner segment of the cone?

Answer 25

Main cell bit where organelles are kept

Question 26

What does the cone synaptic terminal release?

Answer 26

Glutamate

Question 27

What does the outer segment of the cone contain?

Answer 27

Bag containing tightly packed layers of phospholipid membrane

Question 28

What is the reaction to increased light in cones?

Answer 28

In the outer segments, sodium channels are open by default but close due to increased light so cell depolarises and prevents glutamate release

Question 29

What is the reaction to decreased light in cones?

Answer 29

Causes more sodium channels to open so the cell hyperpolarises and more glutamate is released

Question 30

What holds the sodium channels open?

Answer 30

cGMP

Question 31

What does photopigment contain?

Answer 31

Opsin and retinal

Question 32

What formation does photopigment occur in?

Answer 32

11-cisretinaldehyde

Question 33

What happens when light strikes photopigment?

Answer 33

Changes to all trans retinaldehyde which acts like a GPCR Cascade causes decreased cGMP, closing sodium channels

Question 34

What does loss of peripheral vision look like?

Answer 34

Can only see what’s right in front of you

Question 35

What does loss of central vision look like?

Answer 35

Can see everything but what’s directly in front of you

Question 36

What does convergence do?

Answer 36

Increases pixel size

Question 37

What is a receptive field centre?

Answer 37

Anything inside the area one ganglion supplies

Question 38

What happens as light passes through retinal tissue?

Answer 38

Image blurs

Question 39

What is the fovea centralis?

Answer 39

Region where the photoreceptors are uncovered

Question 40

What is special about the fovea centralis?

Answer 40

No retina so no image blur, no rods, ultra-thin cones, only red and green cones and no convergence

Question 41

How does peripheral vision work?

Answer 41

Cone photoreceptors are large and widely spaced and signals from many cones converge onto single ganglion cells

Question 42

What do axons form in the lateral geniculate nucleus?

Answer 42

Retinotopic map

Question 43

What do retinal ganglion cells report?

Answer 43

Changes in illumination from one location to another

Question 44

What does the cortical area process?

Answer 44

Colour

Question 45

What do the inferotemporal visual areas encode?

Answer 45

Info about object identity

Question 46

What do parietal visual areas encode info about?

Answer 46

Location and movement