Taste and smell

Question 1

What are visceral chemoreceptors?

Answer 1

Keep track of concentrations of various substances outside of conscious awareness

Question 2

What are gustatory receptors?

Answer 2

Mediate the sense of taste
Not neurons, but release NTs in response to different taste categories

Question 3

What are olfactory receptors?

Answer 3

Mediate the sense of smell

Question 4

What is unique about the pathway of olfaction?

Answer 4

No relay in thalamus
No neocortical projection area

Question 5

What are the five tastes?

Answer 5

Sweet
Sour
Salty
bitter
Umami

Question 6

What carries the sense of taste for the anterior 2/3 of the tongue?

Answer 6

Chorda tympani N branch of facial N

Question 7

What carries the sense of taste for the posterior 1/3 of the tongue?

Answer 7

Glossopharyngeal N

Question 8

What carries the sense of taste for the taste buds in other areas of the oral cavity?

Answer 8

Vagus N

Question 9

Where do first order neurons for taste synapse?

Answer 9

Nucleus tractus solitarius in brainstem

Question 10

Where do the fibers from the tractus solitarius project to for taste?

Answer 10

Through medial lemniscus to the medial of VPM nucleus in thalamus

Question 11

Where do the fibers from the thalamus for taste project to?

Answer 11

Pass through posterior internal capsule to the lower part of the post central gyrus extending to the insula

Question 12

What Brodmann’s areas are associated with taste sensation?

Answer 12

Area 3, 1, and 2

Question 13

What connections are the basis for emotional and behavioral responses to taste?

Answer 13

Connections between tractus solitarius to amygdala and hypothalamus

Question 14

What is ageusia?

Answer 14

Absence of taste

Question 15

What is hypogeusia?

Answer 15

Decreased taste sensation

Question 16

What is dysgeusia?

Answer 16

Disturbed taste sensation

Question 17

Where is the olfactory membrane?

Answer 17

Superior part of the nasal cavity

Question 18

What type of nerve cell are olfactory cells?

Answer 18

Bipolar neurons derived from CNS

Question 19

What is the function of Bowman glands?

Answer 19

Secrete mucus onto surface of olfactory membrane

Question 20

What part of the olfactory cell responds to odorants?

Answer 20

Cilia that form a dense mat in the mucus
Odorants bind to a G-protein coupled receptor to convert ATP to cAMP

Question 21

Where do primary olfactory neurons project to?

Answer 21

Olfactory bulb

Question 22

What types of cells are found in the olfactory bulb?

Answer 22

Mitral
Tufted
Periglomerular
Granule

Question 23

What is the function of mitral and tufted cells in the olfactory bulb?

Answer 23

Carry olfaction from olfactory bulb to CNS

Question 24

What are the function of periglomerular and granule cells in the olfactory bulb?

Answer 24

Interneurons that integrate and modulate afferent olfactory information
Granule cells also receive inputs from CNS to modulate olfactory afferents

Question 25

What forms the lateral/primary olfactory tract?

Answer 25

Axons of mitral and tufted cells

Question 26

Where does the lateral olfactory tract terminate for conscious appreciation of smell?

Answer 26

Medial temporal lobe Basal frontal lobe

Question 27

Where does the anterior olfactory nucleus project?

Answer 27

To the contralateral olfactory bulb via anterior commissure - believed to be inhibitory

Question 28

How is smell related to the perception of flavor?

Answer 28

Olfactory information passes to adjacent parts of vertebral cortex to combine with taste information

Question 29

What are the components of the sensation of flavor?

Answer 29

Direct chemical stimulation of taste buds Stimulation of olfactory receptors by vapors from food Stimulation of chemical-sensitive and somatosensory free nerve endings of the trigeminal and other nerves in the mucus membranes of oral and nasal cavities

Question 30

What makes the olfactory pathway unique?

Answer 30

Area where CNS has direct contact with external environment Does not relay on thalamus No neocortical projection Olfactory neurons act as receptors themselves Olfactory neurons can be recycled from stem cells

Question 31

What is anosmia?

Answer 31

Absence of smell

Question 32

What is dysosmia?

Answer 32

Distorted sense of smell

Question 33

What is parosmia?

Answer 33

Perverted or abnormal sense of smell

Question 34

What are the characteristics of Kallmann's syndrome?

Answer 34

Hypogonadism Complete loss of smell

Question 35

When do see an increased sensitivity for smells?

Answer 35

Adrenal insufficiency

Question 36

What is the function of pyramidal cells in the piriform cortex in regards to smell?

Answer 36

Olfactory discrimination

Question 37

What is the function of the hypothalamus and amygdala in regards to smell?

Answer 37

Motivational and emotional aspects of smell

Question 38

What is the function of the entorhinal cortex in relation to smell?

Answer 38

Olfactory memories

Question 39

What is the function of the vomeronasal organ?

Answer 39

Perception of odors that as pheromones