Taste and Olfaction

Question 1

Olfactory Receptor Cells

Answer 1

Sensory Neurons
(4-8 week lifespan)

Question 2

Basal Cells

Answer 2

Stem cells that can regenerate sensory cells

Question 3

Bowmans gland

Answer 3

Produce mucus layer surrounding cilia
- Odor detecting GPCRs are located in the cilia

Question 4

Supporting Cells

Answer 4

Provide structure and release chemicals to block toxins

Question 5

Glomerulus Input and Output

Answer 5

• Olfactory sensory receptor cells excite glomeruli cells
• Mitral and tufted cells send output from glomeruli to cortex
• Granule and periglomerular cells produce GABA inhibition

Question 6

Olfactory ensheathing cells aid axon guidance in olfactory neurons

Answer 6

olfactory ensheathing cells have been used experimentally to repair severed axons in the spinal cord.

Question 7

2 Glomeruli for 1 Odorant receptor type (gpcr)

Answer 7

Glomerulus codes for a specific GPCR

Question 8

CNG channel lets :

Answer 8

Na and Ca into the cell
- Ca opens a Cl channel, (Cl out)

CNG channel and chloride channel produce a depolarization in the olfactory cell.

Question 9

Conscious Odor detection

Answer 9

Primary olfactory cortex

Question 10

Limbic System

Answer 10

(hippocampus and amygdala)
- Olfactory signals go to the limbic system, involved in memory and emotion.

Question 11

Anosmia

Answer 11

Loss of smell

Question 12

Parosmia

Answer 12

Distorted Sense of Smell
Ex. Flowers smell like feces

Question 13

Chorda tympani (branch of facial Nerve CNVII)

Answer 13

ant. two thirds of the tongue

Question 14

Glossopharyngeal nerve (CNIX)

Answer 14

Posterior third of the tongue

Question 15

Vagus Nerve (CN X)

Answer 15

few taste buds in the larynx and upper esophagus

Question 16

Taste Bud

Answer 16

• Found in the tongue, palate, esophagus, and epiglottis
• 1 week lifespan

Question 17

Taste Receptor Subtypes

Answer 17

Sour, Salt, Sweet, Bitter, Umami

• Sour and Salt are channels
  Others are GPCRs

Question 18

Bitter Taste Receptors

Answer 18

Found in gut and lung, mediating responses to toxins and bacteria.

Question 19

Gustatory Central Pathways

Answer 19

Solitary nucleus in the medulla -> Thalamus ->Gustatory Cortex