GI 1D- Gustation

Question 1

Humans can distinguish among ______ to ______ different chemicals with our taste buds. But there are 5 primary taste qualities _______, _______, ______, ______ and _______.

Answer 1

4000 to 10000; salty (NaCl); sweet (sucrose); bitter (Quinine); sour (HCL or acids); umami (gluatamate/msg)

Question 2

Taste receptor cells (taste cells) are located in clusters of cells know as _____ _____ that are generally found on papillae.

Answer 2

Taste buds

Question 3

What are the 4 main locations of papillae in the oral cavity?

Answer 3

tongue, palate, pharynx and epiglottis

Question 4

What papillae is 1) mushroom-like, 2) scattered over the entire surface of the tongue (most abundant at the tip and anterior sides) and 3) responds mainly to sweet & salty but also sour substances

Answer 4

Fungiform

Question 5

What papillae is 1) folded structures, 2) most abundant on the middle edges of the tongue and 3) mainly responds to sour?

Answer 5

Foliate

Question 6

What nerve innervates the fungiform and SOME foliate papillae?

Answer 6

Chorda tympani of CN VII (basically anterior 2/3rds)

Question 7

What papillae are 1) the largest and least numerous forming an inverted V at the back of the tongue and 2) respond to mostly bitter substances

Answer 7

Circumvallate

Question 8

What nerve innervates the circumvallate and SOME foliate papillae?

Answer 8

CN IX (basically posterior 1/3rd of tongue)

Question 9

Taste buds in the region of the epiglottis are innervated by ______ while the taste buds in the palate are innervated by ______.

Answer 9

CN X; CN VII

Question 10

Is the Taste map accurate?

Answer 10

No, taste stimuli are spread relatively equally across the tongue.

Question 11

Taste buds include _____ _______ cells and ______ or _______ cells.

Answer 11

taste receptor (TRCs); basal or supporting

Question 12

The opening of the taste bud is called the ______ ______. It allows chemical cues to enter and come into contact with receptors located on the microvilli of taste cells.

Answer 12

taste pore

Question 13

Are TRCs neurons?

Answer 13

No. They are not neurons but synapse onto afferent nerve endings of CNs VII, IX & X.

Question 14

Where do CN afferents terminate?

Answer 14

Nucleus of solitary tract (NST)/ Solitary nucleus

Question 15

The ______ half of the NST contains the gustatory nuclei. Output from the NST travels to the _______ ______ nucleus of that thalamus.

Answer 15

rostral; ventroposterior medial

Question 16

The ventroposterior medial nucleus of the thalamus is responsible for communicating with what?

Answer 16

the Insula (insular cortex), which is a portion of the cerebral cortex within the lateral sulcus.

Question 17

What nerve supplies sensory innervation to the tongue?

Answer 17

lingual nerve of CN V. It carries fibers of the chorda tympani of CN VII to the anterior 2/3rds of the tongue.

Question 18

What can occur from lower 3rd molar removal? When do symptoms appear and when do the heal? Is taste affected?

Answer 18

Light lingual sensitivity impairment. These lingual nerve injuries are present one week after extraction and recover one month after surgery. Taste is unaffected after these procedures.