Cours 8 - Sens chimiques - Chapitres 12 et 13

Question 1

What are the five taste qualities?

Answer 1

Sweet, sour, bitter, salty, and umami.

Question 2

Which taste quality is associated with carbohydrates?

Answer 2

Sweet.

Question 3

Which taste quality is associated with protein content?

Answer 3

Umami.

Question 4

Which taste qualities help maintain electrolyte balance?

Answer 4

Sour and salty.

Question 5

Which taste quality serves as a warning signal and can be toxic in high concentrations?

Answer 5

Bitter.

Question 6

Who are supertasters?

Answer 6

People particularly sensitive to bitter tastes who typically dislike coffee, bitter chocolate, IPAs, or licorice.

Question 7

Which papillae are NOT involved in taste?

Answer 7

Filiform papillae.

Question 8

Where are fungiform papillae most dense?

Answer 8

At the tip and sides of the tongue.

Question 9

Which cranial nerve innervates the anterior 2/3 of the tongue?

Answer 9

Facial nerve (via chorda tympani).

Question 10

Which cranial nerve innervates the posterior 1/3 of the tongue?

Answer 10

Glossopharyngeal nerve (CN IX).

Question 11

Which cranial nerve innervates taste buds in the larynx?

Answer 11

Vagus nerve (CN X).

Question 12

Where do all taste signals from the tongue converge?

Answer 12

Solitary nucleus in the brainstem.

Question 13

Where is the primary gustatory cortex located?

Answer 13

In the anterior insula and the frontal operculum.

Question 14

What kind of receptors are used for bitter, sweet, and umami tastes?

Answer 14

G-protein-coupled receptors.

Question 15

What must happen for tastants to be detected by taste receptors?

Answer 15

They must be dissolved in saliva.

Question 16

What is the misconception about the tongue’s taste map?

Answer 16

That specific tastes are only perceived on specific parts of the tongue, which is false.

Question 17

What is the ‘flavor cortex’?

Answer 17

The orbitofrontal cortex, integrating gustatory and olfactory input.

Question 18

How do congruent stimuli affect flavor perception?

Answer 18

They enhance each other.

Question 19

How do incongruent stimuli affect flavor perception?

Answer 19

They diminish each other.

Question 20

What is dysgeusia?

Answer 20

General dysfunction of the sense of taste.

Question 21

What is ageusia?

Answer 21

Complete loss of taste perception.

Question 22

What is hypogeusia?

Answer 22

Reduced taste perception.

Question 23

What is parageusia?

Answer 23

Altered taste perception, often metallic or bitter.

Question 24

What often gets mistaken for a taste disorder?

Answer 24

Olfactory dysfunction, especially affecting retronasal olfaction.

Question 25

What phenomenon helps maintain taste when one gustatory nerve is impaired?

Answer 25

Release of inhibition.

Question 26

What are the three main functions of the sense of smell?

Answer 26

Warning, Nutrition, and Social Communication

Question 27

What threats are linked to disgust?

Answer 27

Microbial threats like mold and spoiled food

Question 28

What threats are linked to fear?

Answer 28

Non-microbial threats like smoke or predator odor

Question 29

How does smell contribute to nutrition?

Answer 29

Identifies food, detects expectancy violations, regulates intake, aids breastfeeding

Question 30

How does smell help in social communication?

Answer 30

Evaluates partners, perceives emotions, prevents incest

Question 31

What are odorants?

Answer 31

Volatile molecules that trigger smell when reaching the olfactory receptors

Question 32

Why are smells hard to analyze?

Answer 32

Because smell is synthetic — mixtures are perceived as a whole

Question 33

How can odorants reach the nose?

Answer 33

Via orthonasal or retronasal olfaction

Question 34

What is orthonasal olfaction?

Answer 34

Smelling via nostrils from the environment

Question 35

What is retronasal olfaction?

Answer 35

Smelling from inside the mouth via the pharynx

Question 36

Which olfaction type is crucial for flavor?

Answer 36

Retronasal olfaction

Question 37

Where is the olfactory epithelium located?

Answer 37

In the upper nasal cavity

Question 38

How many functioning olfactory receptors do humans have?

Answer 38

Around 300–400

Question 39

How does the olfactory code work?

Answer 39

Different receptors activate specific glomeruli patterns

Question 40

What structure receives input from olfactory neurons?

Answer 40

Glomeruli in the olfactory bulb

Question 41

Which cells transmit from the glomeruli?

Answer 41

Mitral cells

Question 42

Where do mitral cell axons project?

Answer 42

To the primary olfactory cortex (piriform, amygdala, hippocampus, etc.)

Question 43

Why are smells tied to emotion and memory?

Answer 43

Because olfactory regions are part of the limbic system

Question 44

What is the Proust effect?

Answer 44

Emotionally vivid memories triggered by smell

Question 45

What percent of the population has olfactory dysfunction?

Answer 45

Up to 20%

Question 46

What are the two categories of olfactory dysfunction?

Answer 46

Quantitative and qualitative

Question 47

What is anosmia?

Answer 47

Complete loss of smell (5%)

Question 48

What is hyposmia?

Answer 48

Reduced smell sensitivity (15%)

Question 49

What is parosmia?

Answer 49

Distorted smell perception

Question 50

What is phantosmia?

Answer 50

Smelling odors with no source

Question 51

Name causes of acquired olfactory dysfunction

Answer 51

Sinusitis, viral infections, TBI, Parkinson’s, Alzheimer’s