Exam 2 Study Questions

Question 1

If you are missing a S, M, or L, opsin, what might be the symptoms?

Answer 1

Colorblindness

Question 2

Steps of synaptic transmission (5)

Answer 2

1. Action potential arrives at terminal
2. VGCa2+ channels open and Ca2+ rushes into cell
3. Ca2+ warps the synaptic vesicles, releasing NTs
4. NTs diffuse across the synapse
5. NT binds to receptor of pstn

Question 3

Light transduction in light (6-7)

Answer 3

1. Light hits opsin
2. Opsin activates it’s G-protein, which diffuses across the cell
3. The G-protein activates the PDE
4. PDE catalyzes cGMP and turns it into GMP
5. Lack of cGMP CLOSES the ion channel
6. Membrane becomes more negative
7. NT Glu is not released

Question 4

Do photoreceptors release NT Glu in the dark or in the light?

Answer 4

Dark

Question 5

Is Glutamate excitatory or inhibitory in ON BPC

Answer 5

Inhibited

Question 6

Off in dark

Answer 6

1. Glu is released
2. Excitatory Glu excites the cell
3. Releases NT to P or M ganglion
4. Ganglion sends AP

Question 7

On in light

Answer 7

1. No inhibitory glu is released
2. Cell is depolarized
3. Releases NT to P or M ganglion
4. Ganglion sends AP

Question 8

Rods have high/low spatial resolution, high/low sensitivity to light, and are responsible for _________ Vision

Answer 8

Low; High; Black and white

Question 9

Cutting the optic chiasm will affect the

Answer 9

Left nasal and right nasal; Outer portions of L and R visual field

Question 10

What does the basilar membrane do?

Answer 10

Moves up the Organ of Corti, which bends the hair cells.

Question 11

Where is the endolymph? High/Low K+ ECF conc?

Answer 11

Top around the stereocilia; High (K+ flows in)

Question 12

Where is the perilymph? High/Low K+ ECF conc.

Answer 12

Below around the Cell body; Low (K+ flows out)

Question 13

What do hair cells release onto the spiral ganglion cell?

Answer 13

Glutamate

Question 14

Steps of audition in the hair cell

Answer 14

1. Basilar membrane moves up
2. K+ and Ca2+ flows into the hair cells
3. Cell is depolarized
4. The VGCa2+ open allowing for Ca2+ to flow inside
5. The cell body releases glutamate to post spiral ganglion
6. Ganglion sends AP

Question 15

How do we code for frequency of sound?

Answer 15

Tonotopy (Location based excitation)

Question 16

How do we code for intensity of sound?

Answer 16

Amount of NTs released

Question 17

Increased amplitude =

Answer 17

Increased intensity/larger waves

Question 18

What is the first brain area with input from both ears?

Answer 18

The superior olivary complex

Question 19

What is the pathway of sound?

Answer 19

1. Same side ventral cochlear nucleus
2. Bilateral superior olivary complex
3. Lateral lemniscus
4. Inferior colliculus
5. Medial geniculate body
6. Superior temporal gyrus

Question 20

A humans perception of a pitch corresponds to the _____________ of a sound wave; perception of loudness corresponds to the _________ of a sound wave

Answer 20

frequency; amplitude

Question 21

What is the main function of the ossicles?

Answer 21

Transfer vibrations from the tympanic membrane to the oval window

Question 22

What is the main function of the hair cells?

Answer 22

Directly convert sound vibrations into neural impulses

Question 23

In order to increase the decibel measurement of a sound, one would have to alter its wave

Answer 23

amplitude

Question 24

What quality gives rise to tonotopy along the cochlea?

Answer 24

The changing width and stiffness of the basilar membrane

Question 25

Which auditory property most depends upon the utilization of bilateral auditory information?

Answer 25

Sound localization

Question 26

The apex is _______ and ________. It is meant for the transmission of __________

Answer 26

Thick and floppy; Lower frequency

Question 27

The base is __________ and _______________. It is meant for the transmission of _______

Answer 27

Thin and stiff; High frequency