Gustation and Olfaction

Question 1

3 Types of lingual papillae

Answer 1

Circumvillate (line across back of tongue)
Foliate (scrunched group on side of tongue)
Fungiform (More in the front)

Question 2

Areas of the taste bud

Answer 2

Sensory cells detect taste and imitate signal transduction. Nerve at the base.

Question 3

Importance of saliva for tasting

Answer 3

Food must dissolve in saliva for taste to be detected by taste buds.

Question 4

Modern taste receptor distribution and what tastes

Answer 4

taste modalities overlap in areas of the tongue.

Sour
Sweet
Salty
Umami 
Bitter

Question 5

Mechanism of action for tasting salt

Answer 5

Simplest mechanism through sodium channel. Results in depolarization.

Question 6

Mechanism of action for tasting sour foods

Answer 6

Sour foods have high acid content. Hydrogen ions in acid block potassium channels, which causes depolarization

Question 7

Mechanism of action for tasting sweet, bitter, and umami foods

Answer 7

G protein coupled receptors on the microvilli. Depolarization occurs this way.

Question 8

Afferent information sending taste will synapse where in the thalamus

Answer 8

Thalamus 
Lateral-posterior division
Ventral tier
Posterior nucleus (ventral posterior nucleus)
medial portion 

projects to the primary somatosensory cortex

Question 9

Taste receptors in the oropharynx is by which CN

Answer 9

10

Question 10

Taste and sensory of the front of the tongue

Answer 10

Taste- 7

Sensory- V3

Question 11

Taste and sensory of the back of the tongue

Answer 11

9 and 9

Question 12

Olfactory uses which type of receptors

Answer 12

Chemoreceptors.

Question 13

What makes up CN1

Answer 13

Axons of olfactory receptor cells that pass through the olfactory foramen within the cribriform plate of ethmoid, synapse in the olfactory bulb, and then project out to make up the olfactory tract.

Question 14

The olfactory bulb projects out of the

Answer 14

Olfactory foramina of the cribriform plate of ethmoid.

Question 15

Chemoreceptors of olfaction are embedded in which type of epithelial cells

Answer 15

Simple columnar

Question 16

In order for chemoreceptors to detect odors,

Answer 16

Chemicals must be dissolved in water/lipid/mucous to be detected. They undergo rapid sensory adaptation.

Question 17

Immature receptor cells are called

Answer 17

Basal cells.

Question 18

Chemoreceptors can detect how many odorants

Answer 18

400 specific types, but up to millions due to multiple odorants

Question 19

How are chemoreceptors depolarized

Answer 19

By G protein coupled receptors. Sets off cascade that opens ion channels and causes depolarization

Question 20

What is the only sensory pathway that does not initially synapse in the thalamus

Answer 20

olfaction. Travels to the olfactory cortex before the thalamus. Synapses with the thalamus in the anterior lobe, where it projects to the cingulate gyrus to the limbic system/amygdala

How smells can trigger emotions and memories.

Question 21

What lobe is the auditory, olfactory, and gustatory cortexes located at?

Answer 21

In the temporal lobe.