Gustation and Olfaction Flashcards Preview

Neurophysiology > Gustation and Olfaction > Flashcards

Flashcards in Gustation and Olfaction Deck (26):
1

Where are taste buds found?

Tongue
Palate
Tonsillar pillars
Epiglottis
Proximal oesophagus

2

What are the 3 types of papillae?

Circumvallate
Fungiform
Foliate

3

What are the features of circumvallate papillae?

Located at the posterior of the tongue in a V shape
Large numbers of taste buds are found on the walls of these papillae

4

What are the features of fungiform papillae?

Found at anterior surface of tongue
Taste bugs on surface of papillae

5

What are the features of folate papillae?

Found on the lateral marginas are of the tongue

6

Which cells differentiate into new taste cells?

Supporting cells

7

What are the 5 taste categories?

Sour
Salty
Sweet
Bitter
Umami

8

What is umami?

Taste caused by L-glutamate
Found in meats and aged cheese

9

How does the taste threshold relate to different tastes?

Bitter and sour tastes have a much lower taste threshold than sweet and salty
This is because bitter and sour tastes are generally associated with more dangerous substances

10

Which taste cells have metabotrophic pathways?

Sweet
Umami
Bitter

11

Which taste pathways have ionotrophic pathways?

Salty
Sour

12

What are the receptor cells in the olfactory system?

Bipolar neurons

13

Describe the mechanism of the olfactory pathway

1. Odorant molecule binds to 7 transmembrane protein of primary olfactory neuron
2. Activated receptor activates a G-protein, which stimulates AC to convert ATP --> cAMP
3. cAMP activates the cation channel, making it permeable to sodium and calcium
4. Influx of cations causes depolarisation leading to APs

14

What does the Bowman Gland secrete?

Mucus

15

What forms the olfactory knob?

Lower end of bipolar neurons extending into mucus layer

16

Which structure detects the odorants in the nasal cavity?

Olfactory cilia

17

Which cells differentiate into bipolar cells?

Basal cells

18

What connects bipolar neurons to the CNS?

Central processes

19

Where does olfactory information from bipolar cells pass to?

Dendrites of mitral cells found in the neuropil of the glomeruli in the bulb

20

Which cells provide lateral inhibition for signal enhancement of olfactory signals?

Tufted cells
Granule cells

21

Which cells make dendritic connections between mitral cells?

Granule cells

22

How many odour receptor genes does each bipolar neurone express?

1

23

Name the 7 categories of odours

1. Camphoraceous
2. Musky
3. Floral
4. Pepperminty
5. Ethereal
6. Pungent
7. Putrid

24

Which olfactory pathway feeds into the limbic system encoding the emotional aspects of odour?

Medial olfactory pathway

25

What are causes of anosmia?

Nasal disease
Congenital
Head trauma
Idiopathic
AD

26

How can head trauma cause anosmia?

Damage to frontal lobe processin
Damage to ascending nerves at cribiform plate
Permanent compression of nasal passages