TASTE/SMELL PT 1

Question 1

what receptors are important for taste and smell and where are they?

Answer 1

chemoreceptors; tongue and nose

Question 2

describe gustation/taste

Answer 2

Receptors excited by food chemicals

Question 3

how does gustation/taste work

Answer 3

Dissolved molecules interact with receptors on tongue, parts of larynx, pharynx and epiglottis

Question 4

describe olfaction/smell

Answer 4

Receptors excited by air chemicals dissolved in the nasal membrane (detects chemicals in a solution)

Question 5

how does olfaction/smell work

Answer 5

Detects hazards, pheromones, food; Integrates with other senses to form sense of flavor

Question 6

whats the olfactory epithelium

Answer 6

Organ with Pseudostratified epithelium that allows for smell; located on roof of nasal cavity

Question 7

how do chemicals work on olfactory epithelium

Answer 7

Chemicals (odorants) dissolve in mucous of nasal epithelium

Question 8

what happens after chemicals dissolve on olfactory epithelium

Answer 8

Interact with neurons (olfactory receptor cells) like any other neuron
Depolarizes neuron which sends action potential to olfactory bulb

Question 9

what are the three types of cells on olfactory epithelium

Answer 9

Receptor cells (olfactory sensory neuron), Supporting cells, Olfactory stem cells

Question 10

describe Receptor cells (olfactory sensory neuron)

Answer 10

millions on each side of nasal septum, (bowling pin-shaped)

Question 11

describe supporting cells

Answer 11

cushion and surround olfactory cells (columnar shaped)

Question 12

describe olfactory stem cells

Answer 12

base of epithelium (short cells)

Question 13

what are bipolar neurons

Answer 13

neurons with two extensions

Question 14

how are bipolar neurons structured

Answer 14

thin apical dendrite ends in a knob from which several long cilia radiate

Question 15

what are olfactory cilia

Answer 15

Substantially increases receptive surface area

Question 16

how do olfactory cilia lie

Answer 16

Lie flat on nasal epithelium; largely nonmotile

Question 17

what are olfactory cilia covered by

Answer 17

mucus produced by the supporting cells and olfactory glands

Question 18

what does that mucus do

Answer 18

captures airborne odorant chemicals

Question 19

what do filaments of OSNs

Answer 19

project superiorly through the cribriform plate

Question 20

what makes olfactory sensory neurons unique

Answer 20

noticeable turnover (superficial location – can be damaged)

Question 21

how often are olfactory sensory neurons replaced

Answer 21

every 30-60 days by differentiation of olfactory stem cells

Question 22

where does olfactory transduction occur

Answer 22

Ciliated OSN in nasal epithelium in nasal cavity

Question 23

what do olfactory sensory neurons do

Answer 23

express odorant receptors

Question 24

what do axons of OSNs that express the same receptors do

Answer 24

converge onto the same glomerulus at the olfactory bulb, allowing for organization of olfactory information

Question 25

what happens after signals are transmitted to glomeruli

Answer 25

transmitted to higher regions of the brain

Question 26

where do olfactory receptors send the action potential

Answer 26

to the second order neurons, mitral cells, inside glomeruli

Question 27

do different glomeruli respond to different odors

Answer 27

yes

Question 28

where do mitral cells send information and why

Answer 28

down the olfactory tract to either the thalamus or past the thalamus to the hypothalamus, amygdala, or limbic system (allowing the emotional responses to odors)