Vision

Question 1

Refractive eyes are good at

Answer 1

Resolution

Question 2

Compound eyes are good at

Answer 2

Motion detection
Detecting multiple wavelengths
Detecting polarized light

Question 3

Passage of light

Answer 3

Cornea → Anterior Chamber → Iris & pupil → lense → Posterior Chamber

Question 4

Fovea

Answer 4

Greatest visual acuity

More cones than rods

Question 5

Optic disc

Answer 5

Blind spot on retina, axons from receptors form the optic nerve

Question 6

Tapetum

Answer 6

Reflective guanine crystals found in nocturnal animals

Question 7

Name 5 cell types in the retina

Answer 7

Photoreceptors
Bipolar cells
Horizontal cells
Amacrine cells
Ganglion cells

Question 8

Major refractive element

Answer 8

Cornea

Question 9

Depth of field determined by

Answer 9

Iris & pupil

Question 10

Accommodation

Answer 10

Lense

Question 11

Rods are sensitive to

Answer 11

diffuse and scattered light

Question 12

Rods are used in night\light vision

Answer 12

Night vision and Monochromatic vision

Question 13

Cones are sensitive to

Answer 13

Color

Question 14

Temporal and spatial resolution

Rods\cones

Answer 14

Cones

Question 15

There are more rod\cones

Answer 15

Rods

Question 16

Synaptic terminal of photoreceptors

Answer 16

Vesicles for neurotran

Question 17

Inner segment of photoreceptors

Answer 17

Nucleus & organelles

Question 18

Outer segment of photoreceptors

Answer 18

Membranous discs

Question 19

What is the response to light depolarization or hyperpolarization?

Answer 19

HYPERPOLARIZATION

No action potential released in response to light

Question 20

Sequence of hyperpolarization

Answer 20

Ca channels that are usually open in outer segment closes
Less Ca enters the cells
Less NT release

Question 21

What happens to retinol when activated by light

Answer 21

Retinol gets converted from cis to trans

Opsin and retinal combine

Question 22

What is responsible for the decrease in cGMP when activated by light

Answer 22

Phosphodiesterases

Question 23

At rest levels of cGMP, Ca and Na are

Answer 23

High

Question 24

When activated by light, levels of cGMP, Ca and Na are

Answer 24

Low

Question 25

Rhodopsin kinase is responsible for ___ by phosphorylating ______

Answer 25

Termination of a signal | Rhodopsin

Question 26

Rhodopsin Kinase is inhibited by high levels of ____ so is inhibited at rest

Answer 26

cGMP, Ca

Question 27

Phosphorylated rhodopsin binds to

Answer 27

Arrestin

Question 28

Arrestin bound to rhodopsin is responsible for

Answer 28

Retinol & opsin disassociation

Question 29

Myopia

Answer 29

Nearsightedness (concave)

Question 30

Hyperopia

Answer 30

Farsighted (convex)

Question 31

Loss of accomodation

Answer 31

Decrease in lens elasticity

Question 32

Cataracts

Answer 32

Opaque spots on the lens

Question 33

Retinal detattachment

Answer 33

Gap between pigmented epithelium and photoreceptor layers (embryologic defect in stalk formation)

Question 34

Macula degenration

Answer 34

Loss of pigment epithelium& evetually photoreceptors

Question 35

Vitamin A defiency

Answer 35

Vitamin A = trans-retinol | Used to make cis-retinol

Question 36

Blue color blind

Answer 36

Tritanopia

Question 37

Green color blind

Answer 37

Deuteranopia

Question 38

Red color blind

Answer 38

Protanopia

Question 39

Retinitis pigmmentosa

Answer 39

Photoreceptor degeneration

Question 40

M cells Detect: Size of receptive field:

Answer 40

Motion detectors | Large receptive field

Question 41

P cells Detect: Size of receptive field:

Answer 41

Color | Small receptive field

Question 42

M and P cells receive input from | M and P cells are ____ cells and are located in the ___

Answer 42

Receptor cells (rods and cones) and fire action potentials Retinal ganglia cells Lateral geniculate nucleus

Question 43

On Center Receptive Field

Answer 43

Increase in activity when CENTER is illuminated | Decrease activity when SURROUND is illuminated

Question 44

Off Center Receptive Field

Answer 44

Increase in activity when SURROUND is illuminated | Decrease activity when CENTER is illuminated

Question 45

On center receptors

Answer 45

Glutamate receptors

Question 46

Off center receptors

Answer 46

NMDA & AMPA

Question 47

``` W-type Ganglion Cells Do they have center\surround organization? Receptive to? Function? Found in the ```

Answer 47

No center surround organization Blue light Circadian rhythms & pupillary reflexes Pretectal area & hypothalamus

Question 48

Visual neuronal pathway

Answer 48

Receptor cells Retinal ganglia cells Optic chiasm

Question 49

Where do nerves travel after reaching optic chiasm

Answer 49

Lateral geniculate Nucleus (80%) Pretectal area Superior colliculus Hypothalamus

Question 50

Function of hypothalamus in response to light

Answer 50

Contains suprachiasmatic nucleus, involved with circadian rythems

Question 51

Function of superior colliculus

Answer 51

Integration of visual, somatic and auditory information

Question 52

Function or pretectal area

Answer 52

Contains W ganglia involved in pupillary light reflexes

Question 53

Lower visual field information projects

Answer 53

Above the calcarine sulcus in occipital lobe

Question 54

Upper visual field information projects

Answer 54

Below the calcarine sulcus in occipital lobe

Question 55

Meyers loop

Answer 55

``` Visual fibers (inferior retina) from lateral geniculate nucleus to the cortex Some fibers pass through temporal lobe ```

Question 56

Damage to meyers loop

Answer 56

Fibers are from the inferior retina so loose SUPERIOR visual field (half) = Quadrantopia

Question 57

Axons originating from the temporal side of the retina express

Answer 57

Eph B1 so they do not decussate

Question 58

Axons from the nasal side of the retina express neither Eph B1 or B2 so they

Answer 58

decussate

Question 59

Optic chiasm expresses

Answer 59

Ephrin B2 so repels temporal axons that do not decussate