Physiology of Taste and Smell

Question 1

What type or receptors and taste and smell receptors?

Answer 1

chemoreceptors

Question 2

What can taste and smell influence?

Answer 2

flow of digestive juice

Question 3

Can taste perception be influenced by smell?

Answer 3

Yes

Question 4

Where are taste receptors found?

Answer 4

taste buds (organs of taste)

Question 5

What else to taste buds contain?

Answer 5

support cells, basal cells

Question 6

How are cells arranged in taste buds?

Answer 6

like orange slices

Question 7

What is the life span of taste receptor?

Answer 7

10 days

Question 8

Where are taste buds found?

Answer 8

mainly in tongue but also palate, epiglottis, pharynx

Question 9

Which type of papillae in the tongue does not contain taste buds?

Answer 9

filiform

Question 10

What type of nerve fibres do taste receptors synapse with?

Answer 10

afferent

Question 11

Where are signals conveyed to via the brainstem and thalamus?

Answer 11

cortaid gustatory areas

Question 12

Which nerve carries signals from anterior 2/3rds of tongue?

Answer 12

VII

Question 13

Which nerve carries signals from posterior 3rd of tongue?

Answer 13

IX

Question 14

Which nerve carries signals from areas other than tongue eg pharynx?

Answer 14

X

Question 15

Name the 5 primary tastes.

Answer 15

salty, sweet, sour, bitter, unami (meaty or savoury)

Question 16

What often triggers unami tastes?

Answer 16

amino acids especially glutamate

Question 17

What is loss of taste function called, and what might cause it?

Answer 17

ageusia

endocrine, nerve damage, local inflammation

Question 18

What is reduced taste called and what causes it?

Answer 18

hypogeusia

chemotherapy, medications

Question 19

What is distortion of taste called and what might cause it?

Answer 19

dysgeusia

mainly infections, tooth decay etc

Question 20

What are the three types of cell olfactory mucosa contains?

Answer 20

olfactory receptors
support cells
basal cells

Question 21

Neurons in olfactory receptors each have what?

Answer 21

a thick short dendrite and an expanded end called an olfactory rod

Question 22

What project to the surface of the olfactory mucosa from the olfactory rods?

Answer 22

cilia

Question 23

What do odorants bind to?

Answer 23

cilia

Question 24

What do axons of the receptors pierce and then enter?

Answer 24

cribiform plate of ethmoid, enter olfactory bulbs

Question 25

During quiet breathing, what is the only way odarants may be smelled?

Answer 25

diffusion

Question 26

What enhances smelling drawing air currents into nasal cavity>

Answer 26

sniffing

Question 27

What two things must an odarant be to be able to be smelled?

Answer 27

sufficiently volatile and water soluble

Question 28

What is anosmia?

Answer 28

inability to smell

Question 29

What might cause anosmia?

Answer 29

viral infections, allergy, nasal polyps, head injury

Question 30

What is hyposmia and what may cause this?

Answer 30

reduced ability to smell

as with anosmia, or may be early sign of Parkinson’s

Question 31

Dysosmia is what? What are examples?

Answer 31

altered sense of smell

eg hallucinations of smell, or differently interpreting odours