5: Physiology of taste and smell Flashcards Preview

ENT Week 1 2017/18 > 5: Physiology of taste and smell > Flashcards

Flashcards in 5: Physiology of taste and smell Deck (34)
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1
Q

What are the receptors for taste and smell?

A

Chemoreceptors

2
Q

In general, how do poisons taste and smell?

A

Bad

to encourage you not to ingest it

Acids taste SOUR

Toxins taste BITTER

3
Q

What are the sensory organs of taste?

A

Taste buds

4
Q

What are the chemoreceptors found in taste buds?

A

Taste receptor cells

5
Q

Taste receptor cells have a short life span of ___ days.

A

10

6
Q

Which type of nerve fibres are found in the sensory receptor cells of the taste buds?

A

Afferent nerves

7
Q

Where are the taste buds found?

A

Tongue

Palate

Epiglottis

Pharynx

8
Q

Which tongue papillae have taste buds?

A

Fungiform (anterior), vallate (border) and foliate (fringes)

Filiform (middle) DO NOT

9
Q

Which cranial nerve supplies taste for the

anterior 2/3rds

posterior 1/3rd

of tongue?

A

Chorda tympani branch of CN VII

CN IX

10
Q

What change in potential does the binding of chemicals to taste buds cause?

A

Depolarisation

11
Q

Which nerve fibres are action potentials transferred to in the taste buds?

A

Afferent nerves

12
Q

Which cranial nerve supplies the taste buds of the epiglottis and pharynx?

A

CN X

13
Q

Which chemical causes a salty taste?

A

Sodium chloride (NaCl)

14
Q

Which ions cause a sour taste?

A

Hydrogen ions

i.e acidic

15
Q

Which chemical causes a sweet taste?

A

Glucose

16
Q

What broad group of chemicals cause a bitter taste?

A

Toxins

17
Q

What is ageusia?

A

Loss of taste

18
Q

What is hypogeusia?

A

Reduced taste

19
Q

What is dysgeusia?

A

Distorted taste

20
Q

What is gustation?

A

Taste

21
Q

What is olfaction?

A

Sense of smell

22
Q

What mucosa of the nasal cavity is important in the sense of smell?

A

Olfactory mucosa

23
Q

Which cells in the olfactory mucosa act as chemoreceptors?

What kind of nerve fibres do they contain?

A

Olfactory receptor cells

Afferent fibres

24
Q

From which structures of the olfactory neurons do cilia project outwards?

A

Olfactory rods

25
Q

Where do odorants bind?

A

Cilia

26
Q

Which cells act as precursors for new olfactory receptor cells?

A

Basal cells

27
Q

Through which structure do the olfactory nerves pass into the anterior cranial fossa?

A

Cribriform plate of ethmoid bone

28
Q

Which structures do the olfactory nerves become when they pass through the cribriform plate?

A

Olfactory bulbs

29
Q

Which lobe contains the olfactory centre of the brain?

A

Temporal lobe

30
Q

What act enhances the sense of smell by forcing odorants upwards onto the olfactory mucosa?

A

Sniffing

31
Q

What two properties must a substance have to be smellable?

A

Volatile (to be carried in the air)

Water soluble (to dissolve in the mucus that the cilia create)

32
Q

What is anosmia?

A

Inability to smell

33
Q

What is hyposmia?

A

Reduced ability to smell

34
Q

What is dysosmia?

A

Altered sense of smell