Sensory Physiology - Taste and Smell

Question 1

Perception vs. sensation

Answer 1

Percetpion - created by brian from APs from sensory receptors

Question 2

Structural category

Answer 2

Modified epithelial chemoreceptors

Question 3

Taste and smell structure neural level

Answer 3

Communicate with a specialized receptor cell that then communicates with affarnet nurons

Question 4

AP generation

Answer 4

Stimulus causes receptor potential that then MIGHT cuase an AP

Question 5

Sensory adaptation

Answer 5

Tonic - slowly adapting

Phasic - rapidly adapting

Can occur at peripheral - level of receptor

OR central - at processing level

Question 6

Specificity

Answer 6

Sensation is characteristic of each sensory neuron produced by adequate stimulus

Regardless of how stimulated, only one sensory modality perceived (labelled line)

Question 7

Stevens power law

Answer 7

Exponential relationship to sense a difference

Question 8

Phasic vs tonic response

Answer 8

Phasic - potential inc with inc stimulus then as it continues, potential dec

Tonic - potential is proprotional to intensity of stimulus

Question 9

Taste cell physiology

Answer 9

Rapid turnover
GPCR
Leads to depolarization and calcium mediated NT release

Most taste from fungiform cells

Question 10

Covergence of taste

Answer 10

A given sensory neuron may be stimulated by more than 1 atste cell in several diff taste buds

Each bud contains taste cells responseive to a certain category

Question 11

Importance of taste

Answer 11

Protection

mental health

Question 12

Salty
Sour
Umami
Sweet and bitter

Answer 12

Na passes through channels and activates receptor cells

H+ channel

Amino acids

Mediated by gustducin (GCP)

Question 13

Saliva importance in taste

Answer 13

Thershlold issues

Sensed moleculaes are dissolved in the saliva

Question 14

Innervation of taste buds

Answer 14

Front half - facial nerve
POst third - glosspharyngeal
Pharynx and larynx in vague nerve
Trigeminal for most of thermal, pain, and tactile info

Question 15

CNS taste projections

Answer 15

1st order to solitary nucleus of medulla…then to thalamus…these go to gustatory cortex in parietal lobe

Question 16

Dysguesia

Answer 16

Oral products and meds can change chemoreceptors

Loss of slaliva cna lead to dec sweet sensation due to loss of salivary amylase

Question 17

Olfaction neural

Answer 17

Axons to olfactory bulb of cerebrum…then to olfactory cortex/hippocampus

Intx of odorant molecules in nasal mucus with receptors on the ciliated endings of olfactory neurons

Question 18

Mech of neural activation of smell

Answer 18

Binds to and act through GPs to inc cAMP

Question 19

Importance of smell

Answer 19

Well-being (mental)
Emotions
Pheromones
Cues for learning 
Oral malodours