Pain and Vision

Question 1

Cornea

Answer 1

shields the eye from germs and dust; bends the light

Question 2

Iris

Answer 2

Colored disc inside the eye; separates the cornea from the lens

Question 3

What are the 2 chambers in the iris?

Answer 3

the anterior chamber (between the cornea and the iris) and the posterior chamber (between the iris and the lens)

Question 4

Eye color determined by

Answer 4

the iris

Question 5

The ____ controls the amount of light entering the eye

Answer 5

iris

Question 6

During the activation of the parasympathetic nervous system, the sphincer pupillae is _____, and the dilator pupillae is ______

Answer 6

contracted, relaxed

Question 7

During the activation of the sympathetic nervous system, the sphincer pupillae is _____, and the dilator pupillae is ______

Answer 7

relaxed, contracted

Question 8

As distance increases… (changes in lens shape, ciliary muscles, suspensory ligament)

Answer 8

lens is less convex (more flat); tension on suspensory ligaments, ciliary muscles relax

Question 9

As distance decreases… (changes in lens shape, ciliary muscles, suspensory ligament)

Answer 9

lens is more convex, ciliary muscles contract, less tension on suspensory ligaments

Question 10

the retina

Answer 10

processes light by converting visual stimulus into neural activity

Question 11

What is the pathway of light

Answer 11

ganglion cells, bipolar cells, photoreceptors

Question 12

What does the Muller glia do in the retina?

Answer 12

helps light go through without modification; like a tunnel

Question 13

The outer segment of the rods and cones…

Answer 13

where we find a lot of pigment- sensing the light

Question 14

The inner segment of the rods and cones…

Answer 14

contains things that help with the cellular functions; synapses occur here

Question 15

true or false: is it retinal that is sensitive to light

Answer 15

true- it changes shape because of light

Question 16

Do rods and cones fire action potentials?

Answer 16

no- they do not fire action potentials

Question 17

In the dark is 11-cis retinal present or 11-trans retinal

Answer 17

11-cis retinal

Question 18

In the light is 11-cis retinal present or 11-trans retinal

Answer 18

11-trans retinal

Question 19

In the dark, are the photoreceptors depolarized or hyperpolarized

Answer 19

depolarized

Question 20

In the dark are neurotransmitters released?

Answer 20

Yes- because it is depolarized- it releases neurotransmitter

Question 21

In the light, are the photoreceptors hyperpolarized or depolarized?

Answer 21

hyperpolarized

Question 22

In the light, do photoreceptors release neurotransmitters?

Answer 22

no- because they are hyperpolarized

Question 23

What is the ligand for the CNG channel?

Answer 23

cGMP

Question 23

in the _____, there is an increased level of cGMP

Answer 23

dark

Question 24

What would happen to the photoreceptor if the CNG channels would not open? (what ions are flowing, de/hyperpolarized, when does this happen)

Answer 24

Only K+ would be flowing out making the photoreceptor more negative- leads to hyperpolarization- this happens in light

Question 24

What happens when the CNG channels are opened

Answer 24

influx of positive ions (Na+ and Ca2+)

Question 25

What is the role of transducin?

Answer 25

When activated, it decreases the concentration of cGMP

Question 25

How does transducin decrease the cGMP concentration?

Answer 25

by activating phosphodiesterase

Question 26

Do bipolar cells generate action potentials?

Answer 26

no sir (they respond to glutamate with graded potentials)

Question 27

On bipolar cells

Answer 27

detect light objects in a dark background

Question 28

Off bipolar cells

Answer 28

detect dark objects in a light background

Question 29

On bipolar cells are ..... by glutamate

Answer 29

hyperpolarized (because it inhibits on bipolar cells)

Question 30

Off bipolar cells are ..... by glutamate

Answer 30

depolarized (because it activates off bipolar cells)

Question 31

What do the retinal ganglion cells do

Answer 31

They detect shape and movement

Question 32

Type P ganglion cells characteristics

Answer 32

color sensitive, small concentric receptive field, slowing adapting

Question 33

Type M ganglion cells characteristics

Answer 33

larger than P cells, synapses with many bipolar cells, color insensitive, fast adapting

Question 34

What is the order of visual processing

Answer 34

receptors, bipolar cells, retinal ganglion cells, lateral geniculate nucleus (in thalamus)

Question 35

M-Pathway is for

Answer 35

movement

Question 36

P-blob pathway is for

Answer 36

color

Question 37

P-interblob pathway is for

Answer 37

form and depth

Question 38

Horizontal cells

Answer 38

synapse with surrounding photoreceptor cells; they affect how you are going to send message to the bipolar cells; important in providing contrast (lateral inhibition)

Question 39

Amacrine cells

Answer 39

synapse with bipolar cells and ganglion cells; provide lateral connections

Question 40

When there is diffuse light on both center and surrounding of the eye what are the responses from the on-center and off-center retinal ganglion cells

Answer 40

both have a weak response from ganglion cell

Question 41

What are the two types of pain fibers

Answer 41

A delta and C fibers

Question 42

The lateral geniculate nucleus receives info about... and how does it process it

Answer 42

stimulus location and contrast (rod pathways are separate from cone pathways- parallel processing)

Question 43

M cells and P cells are types of

Answer 43

retinal ganglion cells

Question 43

the M pathway, the P blob pathway, and the P inter-blob pathway are found where

Answer 43

the lateral geniculate nucleus

Question 44

V4 percieves

Answer 44

color

Question 45

The inferior temporal cortex is the

Answer 45

face recognition cortex