Lecture 28

Question 1

What is hearing?

Answer 1

sound waves converted to electrical energy in hair cells

Question 2

What is equilibrium?

Answer 2

detection of body position using the semicircular canals

Question 3

What is the pinna?

Answer 3

collects and directs sound waves into the ear

Question 4

How small is the ear canal?

Answer 4

very small

Question 5

What is the tympanic membrane?

Answer 5

eardrum

Question 6

What are the 3 tiny bones right after the tympanic membrane that passes the vibrations to the vestibular apparatus?

Answer 6

incus | stapes | malleus

Question 7

Which section of the ear (inner, outer, middle) is fluid filled?

Answer 7

inner

Question 8

What are the 2 main parts of the inner ear that translates the vibrations from the sound into info for the CNS?

Answer 8

vestibular apparatus | cochlea

Question 9

What does the vestibular apparatus do with the vibrations it receives from the 3 tiny bones?

Answer 9

translates the air vibrations into fluid-filled vibrations = send signal to different parts of the cochlea

Question 10

What does the cochlea do with the vibrations it receives from the vestibular apparatus?

Answer 10

has tiny hair cells each can detect a different frequency of sound

Question 11

What is the cochlea?

Answer 11

intricate device that can detect different wavelengths of sound

Question 12

What are the nerves that the cochlea sends the sound info to?

Answer 12

auditory nerves

Question 13

What is the sound info coded as?

Answer 13

neurotransmitter release

Question 14

What are semicircular canals and which section of the ear are they located?

Answer 14

bones help detect position | positioned in the X, Y, Z axis | found in the inner ear

Question 15

How many Hz can ears detect?

Answer 15

20,000

Question 16

How can the auditory cortex distinguish the different frequency sound waves?

Answer 16

hair cells active at basal/baseline level = auditory cortex compares the incoming signal from the basal activity

Question 17

Where in the cochlea are the hair cells located?

Answer 17

cochlear duct

Question 18

What is the tympanic duct?

Answer 18

where the sound leaves through the round window

Question 19

Where are hair cells that detect higher frequencies located along the cochlear duct?

Answer 19

closer to the ear opening

Question 20

What happens when a sound wave triggers a hair cell?

Answer 20

hair cells move in one direction &raquo_space;> ion channels open &raquo_space;> depolarization of hair cell &raquo_space;> NT release

Question 21

What does the semicircular canals tell us?

Answer 21

orientation of the head in space

Question 22

What are otolith crystals?

Answer 22

attached to the membrane | goes where gravitational pull is the highest = signals CNS where the head is going

Question 23

What are otolith organs?

Answer 23

have otolith crystals | macula

Question 24

What are the 2 otolith organs?

Answer 24

utricle | saccule

Question 25

What is vertigo?

Answer 25

when the otolith crystals are dislodged >>> causing confusion in the CNS not knowing where your head in space is

Question 26

What are cristae?

Answer 26

responsible for acceleration movement | at openings of semicircular canals | has hair cells

Question 27

What are the 2 branches of Cranial Nerve VIII?

Answer 27

vestibular branch and cochlear branch

Question 28

What type of receptors are smell and taste?

Answer 28

chemoreceptors

Question 29

What are the 2 oldest senses in organisms?

Answer 29

smell and taste

Question 30

What is the olfactory bulb?

Answer 30

extension of the forebrain

Question 31

What are the olfactory sensory neurons?

Answer 31

primary sensory neurons of the olfactory system

Question 32

What is the only special sense that does not need to pass through the thalamus?

Answer 32

olfactory = goes directly to the olfactory cortex (in front of brain)

Question 33

How are different and new smells and flavors encoded to the CNS?

Answer 33

different combos of different molecules = can trigger different combos of neurons >>> send the info together to get combo of different inputs

Question 34

What is Cranial Nerve I?

Answer 34

the bundle of olfactory nerve axons

Question 35

How can taste and smell trigger associated memories?

Answer 35

these senses are not memorized but can be recognized and associated with a memory

Question 36

Where are the odorant receptors located?

Answer 36

at the olfactory cilia (dendrites)

Question 37

What is the function of the Bowman's gland?

Answer 37

secrete mucus to protect the nerve endings so the cilia can stay moist

Question 38

What are the 3 things that the olfactory neurons connect to?

Answer 38

olfactory bulb | cilia | mucus gland

Question 39

What is gustation?

Answer 39

sense of taste

Question 40

What are the 5 types of taste?

Answer 40

sweet | sour | salty | bitter | umami

Question 41

What is umami?

Answer 41

taste for amino acids

Question 42

What activates the gustatory neurons?

Answer 42

chemical signals from taste receptors

Question 43

What cranial nerves do the gustatory neurons become?

Answer 43

7, 9, 10

Question 44

Which taste receptors are ion channels?

Answer 44

sour and salty

Question 45

Which taste receptors are G-coupled receptors?

Answer 45

sweet | umami | bitter

Question 46

How can neighboring taste receptors trigger each other?

Answer 46

ATP can act as NTs = activate primary sensory neurons or activate neighboring cell types to release more NTs

Question 47

What is taste transduction?

Answer 47

each taste cell senses only one type of ligand

Question 48

What are transient receptor potential (TRP) receptors?

Answer 48

taste receptor activated based on temperature (ie: mint and cold water)

Question 49

What are the 4 non-traditional taste sensations?

Answer 49

fat | CO2 | calcium | capsaicin