Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Otolaryngology > Physiology of taste and smell > Flashcards

Physiology of taste and smell Flashcards

1
Q

What type of receptors allow for taste?

A

Chemoreceptors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the function of taste?

A

Stimulation of taste receptors can induce a pleasurable or objectionable sensation, acting as a checkpoint for quality control (Off foods and poisons taste bad)

It also influences the flow of digestive juices and is influenced also by smell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What makes up a taste bud?

A

Tightly packed receptor cells and support cells

Receptor cells end in microvili, branching through the pore in the tongue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the lifespan of a taste bud?

A

They have a lifespan of around 10 days are replaced by basal cells from within the taste buds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are some locations of tastebuds?

A

Tongue
Mucosa of the palate
Epiglottis
Pharynx
Nasal cavity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Where on the tongue are tastebuds found?

A

In the papillae of the tongue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the 4 types of papillae on the tongue?

A
  • Filiform - Most numerous, do not contain taste buds
  • Fungiform - Contain taste buds
  • Vallate - Contain taste buds
  • Folliate - Contain taste buds
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Describe the process of taste

A
  1. Binding of tastant chemicals to receptor cells
  2. Initiates action potentials in afferent nerve fibres
  3. Cranial nerve transmit APs via the brainstem and thalamus to the cortical gustatory areas
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What cranial nerves are responsible for transmitting taste?

A

Chorda tympani branch of CN VII - Anterior 2/3rds tongue

CN IX - Posterior 1/3rd of tongue

CN X - Epiglottis and pharynx

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the 5 primary tastes?

A
  • Bitter
  • Sour
  • Salty
  • Sweet
  • Umami (Meaty or savoury taste)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What causes bitter taste?

A

Stimulated by diverse group of tastants including alkaloids, poisonous substances and toxic plant derivatives

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What causes a sour taste?

A

Stimulated by acids containing free H+

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What causes salty taste?

A

Stimulated by chemical salts, especially NaCl

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What causes sweet taste?

A

Stimulated by configurations of glucose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What causes umami taste?

A

Stimulated by amino acids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is ageusia?

A

Loss of taste

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is hypogeusia?

A

Reduced taste

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is dysgeusia?

A

Distortion of taste

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What are some causes of ageusia?

A
  • Nerve damage
  • Local inflamation (E.g. glossitis, radiation, tobacco)
  • Some endocrine disorders
20
Q

What are some causes of hypogeusia?

A
  • Chemotherapy
  • Medications
21
Q

What are some causes of dysgeusia?

A
  • Glossitis
  • Gum infection
  • Tooth decay
  • Reflux
  • URTI
  • Medications
  • Neoplasms
  • Zinc deficiency
22
Q

What are the functions of smell?

A

Stimulation of smell receptors can induce a pleasurable or objectionable sensation, acting as a checkpoint for quality control (Off foods and poisons taste bad)

It also influences the flow of digestive juices and influences taste

Smell is also useful in communication (E.g. mother to infant)

23
Q

What are the 4 neural systems in the left and right sides of the nose?

A
  • Main olfactory system - CN I
  • Trigeminal somatosensory system - CN V
  • Accessory olfactory system - E.g. Vomernasal
  • Nervus terminalis - CN 0
24
Q

What does CN I sense in smell?

A

CN I mediates the common odours such as roses, chocolate and vanilla

25
What does CN V sense in smell?
CN V has a chemical and non-chemical stimulus such as irritation, burning, cooling and tickling It also has the protective effect of halting inhalation if you sniff something harmful
26
Where does the olfactory neuroepithelium sit?
Within a small region of the nasal mucosa in the olfactory cleft, just below the cribriform plate of the ethmoid bone, covering small parts of the superior and middle nasal concha and septum
27
What percentage of inhaled air reached the olfactory neuroepithelium?
10-15%
28
How are swallowed foods smelt?
Particles can move up the pharynx into the nasal cavity
29
How do odourants reach the olfactory neuroepithelium during normal breathing?
By diffusion as the olfactory mucosa is above the path of normal air intake
30
How does sniffing enhance smelling?
By drawing air currents upwards within the nasal cavity
31
What are some characteristics of a substance that allow it to be smelled?
- Sufficiently volatile (Some of its molecules can enter the nose with inspired air) - Sufficiently water soluble (Can dissolve in the mucus coating of the olfactory mucosa
32
What type of cell surface is the olfactory neuroepithelium?
Pseudostratified columnar epitheium
33
What are some structures found within the olfactory neuroepithelium?
- Bi-polar sensory neurones extending odourant receptor-containing cilia into the mucus - Supporting cells to insulate and protect - Duct cells of bowmans glands, which secrete mucus - Basal cells (Stem cells)
34
Describe the path of an odourant to a chemical signal
1. Odourant enters the nose 2. Passes to the olfactory cleft 3. Moves from our phase to the aqueous phase through mucous 4. Odourants then either diffuse or are transported by specialised proteins to the receptor 5. This causes an AP in the olfactory nerves 6. This passes through the cribriform plates in fascicles of around 20-30 neurones, which release dendrites containing receptor cilia
35
What is anosmia?
Inability to smell
36
What is hyposmia?
Reduced ability to smell
37
What is dysosmia?
Altered sense of smell
38
What is phantosmia?
Smell percieved in the absense of a stimulus (Olfactory halucination)
39
What are some conductive causes of olfactory abnormality?
- Nasal polyps - Rhinitis - Nasal mass
40
What are some sensorineural causes of olfactory abnormality?
- Viral - Head trauma - Neurological (E.g. Parkinsons, Alzheimers) - Brain tumours - Medications
41
What test can be used to assess olfaction?
UPSIT test - Scratch and sniff cards
42
What is a supportive management option in anosmia lasting >2 weeks?
Smell retraining
43
How is life-expectancy affected by anosmia and ageusia?
It is decreased
44
What are some possible affects of anosmia?
Loss of libido Impact on occupation
45
What are some occupations that may be affected by anosmia?
Fire fighters (Can't smell smoke) Chefs (Can't smell or taste food) Sommeliers (Can't smell wine)
46

Otolaryngology (23 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions