Olfaction and Taste

Question 1

There are 3 neurons involved in the olfaction pathway.
Neuron 1 is a ______ neuron, neuron 2 has its body in the __________ and it projects directly to olfactory cortices. Neuron 3 has its axon in the ___________.

Answer 1

bipolar, olfactory bulb, uncinate fasciculus

Question 2

The lamina propria of olfactory mucosa contains ___________ which secrete mucus.

Answer 2

Bowman glands

Question 3

Olfactory epithelium is __________.
It contains ___________ which provide metabolic and physical support to receptor cells, ________ cells that are proginator cells, and _________ cells which form synapses with CN V fibers and are sensitive to chemical irritants but are not discriminative.

Answer 3

pseudostratified columnar neuroepithelium, sustentacular supporting cells, basal cells (stem cells), microvillar (brush) cells

Question 4

The basal cell nuclei of the olfactory epithelium is located close to the _________

Answer 4

lamina propria

Question 5

olfactory receptor neurons are derived from the __________ and have ______ morphology

Answer 5

nasal (olfactory) placode, bipolar morphology

Question 6

Olfactory receptor neurons are _________ and are covered by ensheathing cells

Answer 6

unmyelinated

Question 7

Every olfactory receptor neuron has ___ type(s) of receptor for odorants

Answer 7

1

Question 8

Odorant binding proteins are produced by the ________ cells

Answer 8

sustentacular

Question 9

The cAMP-activated channels create _______ potentials when an odorant is detected

Answer 9

graded

Question 10

a single odor can activate ______ odorant receptor(s)

Answer 10

multiple

Question 11

______ odorant(s) can activate multiple glomeruli and this is referred to as ________

Answer 11

one, cross fiber activation

Question 12

Cell bodies of periglomerular cells are in the ________ layer

Answer 12

glomerular layer

Question 13

Tufted cells are found in the ______ layer

Answer 13

external plexiform layer

Question 14

Mitral cells are found in the ______ layer

Answer 14

mitral cell layer

Question 15

Granule cells are categorized as _______ and are in the _______ layer

Answer 15

interneurons, granule cell layer

Question 16

sensory information from olfactory receptor neurons travels through the _______ and enters the ________.
From there it interacts with the ________ cells before being transferred to neurons of the _______ cells and _______ cells. Both of these cell types interact with ________ cells before passing their information onto the _______ tract.

Answer 16

cribiform plate, olfactory glomeruli, periglomerular cells, tufted cells, mitral cells, granule cells, lateral olfactory tract

Question 17

The main efferent neurons of the olfactory bulb are ______ cells and _______ cells.

Answer 17

tufted cells, mitral cells

Question 18

Granule cells lack _____

Answer 18

axons

Question 19

centrifugal fibers provide excitatory input to ________ cells from the _________, ______, and ________.

Answer 19

granule cells, olfactory cortices, locus ceruleus, raphe nuclei

Question 20

Centrifugal fibers provide feedback inhibition to _______ and _______ cells via __________ synapses

Answer 20

mitral, tufted, GABAergic dendrodendritics

Question 21

Odorant binding proteins are produced by the ________ cells

Answer 21

sustentacular

Question 22

The cAMP-activated channels create _______ potentials when an odorant is detected

Answer 22

graded

Question 23

a single odor can activate ______ odorant receptor(s)

Answer 23

multiple

Question 24

______ odorant(s) can activate multiple glomeruli and this is referred to as ________

Answer 24

one, cross fiber activation

Question 25

Cell bodies of periglomerular cells are in the ________ layer

Answer 25

glomerular layer

Question 26

Tufted cells are found in the ______ layer

Answer 26

external plexiform layer

Question 27

Mitral cells are found in the ______ layer

Answer 27

mitral cell layer

Question 28

Granule cells are categorized as _______ and are in the _______ layer

Answer 28

interneurons, granule cell layer

Question 29

sensory information from olfactory receptor neurons travels through the _______ and enters the ________. From there it interacts with the ________ cells before being transferred to neurons of the _______ cells and _______ cells. Both of these cell types interact with ________ cells before passing their information onto the _______ tract.

Answer 29

cribiform plate, olfactory glomeruli, periglomerular cells, tufted cells, mitral cells, granule cells, lateral olfactory tract

Question 30

Granule cells lack _____

Answer 30

axons

Question 31

centrifugal fibers provide excitatory input to ________ cells from the _________, ______, and ________.

Answer 31

granule cells, olfactory cortices, locus ceruleus, raphe nuclei

Question 32

Centrifugal fibers send excitatory signals to ________ cells which provide feedback inhibition to _______ and _______ cells via __________ synapses

Answer 32

Granule cells, mitral, tufted, GABAergic dendrodendritic

Question 33

Centrifugal fibers are _____ to granule cells and exit the olfactory cortices via the _______

Answer 33

Primary afferents, lateral olfactory tract/stria

Question 34

Centrifugal fibers provide excitatory input to granule cells from _________, ______, and ________.

Answer 34

Primary olfactory cortices, locus ceruleus, raphe nuclei

Question 35

Centrifugal fibers send excitatory information to granule cells which provide feedback inhibition via GABAergic synapses to _______ and ______ cells

Answer 35

Mitral cells, tufted cells

Question 36

Odorant binding proteins are produced by the ________ cells

Answer 36

sustentacular

Question 37

The cAMP-activated channels create _______ potentials when an odorant is detected

Answer 37

graded

Question 38

a single odor can activate ______ odorant receptor(s)

Answer 38

multiple

Question 39

______ odorant(s) can activate multiple glomeruli and this is referred to as ________

Answer 39

one, cross fiber activation

Question 40

Cell bodies of periglomerular cells are in the ________ layer

Answer 40

glomerular layer

Question 41

Tufted cells are found in the ______ layer

Answer 41

external plexiform layer

Question 42

Mitral cells are found in the ______ layer

Answer 42

mitral cell layer

Question 43

Granule cells are categorized as _______ and are in the _______ layer

Answer 43

interneurons, granule cell layer

Question 44

sensory information from olfactory receptor neurons travels through the _______ and enters the ________. From there it interacts with the ________ cells before being transferred to neurons of the _______ cells and _______ cells. Both of these cell types interact with ________ cells before passing their information onto the _______ tract.

Answer 44

cribiform plate, olfactory glomeruli, periglomerular cells, tufted cells, mitral cells, granule cells, lateral olfactory tract

Question 45

The main efferent neurons of the olfactory bulb are ______ cells and _______ cells.

Answer 45

tufted cells, mitral cells

Question 46

Granule cells lack _____

Answer 46

axons

Question 47

Mitral and tufted cells receive inhibitory input from both _______ cells and _______ fibers.

Answer 47

periglomerular cells, centrifugal fibers

Question 48

The axons of ______ and ________ form the lateral olfactory tract and stria

Answer 48

mitral, tufted

Question 49

The __________ is the structure by which olfactory bulbs communicate

Answer 49

anterior commissure (medial olfactory striae)

Question 50

_________ are secondary axons that branch from primary axons

Answer 50

Collateral axons (collaterals)

Question 51

Mitral and tufted cells send collaterals to the ________ nucleus

Answer 51

anterior olfactory nucleus (within olfactory tract)

Question 52

Olfactory cortices receive _______ connections with olfactory bulb

Answer 52

direct (secondary neurons)

Question 53

The olfactory bulb sends direct connections to the following 4 cortices:

Answer 53

piriform cortex, anterior cortical amygdaloid nucleus, periamygdaloid cortex, lateral entorhinal cortex

Question 54

The _______ cortex is the largest and is the major olfactory cortical area. It encodes higher order representations of odor quality, identity, and familiarity

Answer 54

piriform cortex

Question 55

The ________ cortex is located in the most medial portion of the temporal lobe

Answer 55

piriform cortex

Question 56

The olfactory cortices project to the ______, ________ nucleus, ______ cortex, and ________ cortex before projecting to the olfactory bulb via the centrifugal fibers

Answer 56

lateral hypothalamus, dorsomedial thalamic nucleus, insular cortex, orbital cortex

Question 57

The ________ cortex is an olfactory cortex that preprocesses information that is entering the hippocampus

Answer 57

entorhinal cortex

Question 58

The ________ cortex combines input from taste, texture, and smell and plays major role in flavor perception

Answer 58

orbitofrontal cortex

Question 59

The orbitofrontal cortex is just anterolateral to the _______ and just lateral to the ________

Answer 59

optic chiasm, olfactory tract

Question 60

The 3 efferent olfactory cortices are:

Answer 60

Ventral lateral thalamus, dorsomedial nucleus, orbitofrontal nucleus

Question 61

The dorsomedial hypothalamic nucleus is located immediately adjacent to the _______

Answer 61

hypothalamus

Question 62

Taste information is carried by a ________ primary neuron

Answer 62

pseudounipolar

Question 63

The primary neuron cell bodies of the taste pathway are located in the _______ ganglion, _________ ganglion, and the _______ ganglion

Answer 63

inferior (petrosal) ganglion, geniculate ganglion, inferior (nodose) ganglion

Question 64

Taste information in the posterior 1/3 of the tongue in the ______ and ______ papillae and continues in the ______ of CN ___ and synapses in the ______ ganglion

Answer 64

posterior foliate papillae, vallate papillae, lingual branches, CN IX, inferior (petrosal ganglion)

Question 65

Taste information from the anterior 2/3 of the tongue begins in the _____ and ______ papillae before traveling via ______ of the CN ___ and synapses in the _____ ganglion

Answer 65

fungiform papillae, anterior foliate papillae, chorda tympani, CN VII, geniculate ganglion

Question 66

Taste information from the extralingual taste buds of the soft palate travel via _____ to the ______ ganglion

Answer 66

CN VII, geniculate ganglion

Question 67

Taste information to the epiglottis and esophagus travels via the ________ nerve of the CN ___ and synapses in the __________ ganglion

Answer 67

superior laryngeal nerve, CN X, inferior (nodose) ganglion

Question 68

Papillae are formed by ________ epithelium

Answer 68

stratified squamous

Question 69

taste buds on ______ papillae do not sit in pits, while taste buds in ______ papillae sit in pits which are in close proximity, and taste buds in _______ papillae sit in pits situated somewhat far from each other

Answer 69

fungiform papillae, foliate papillae, circumvallate papillae

Question 70

Most of the tongue is covered in _____ papillae

Answer 70

fungiform papillae

Question 71

Salty and sour tastants activate ________ taste receptors

Answer 71

ion channel

Question 72

Sweet, umami, and bitter tastants activate ________ taste receptors

Answer 72

GPCR

Question 73

____ taste receptors encode sweet and umami, _____ taste receptors encode bitter taste and both of these are expressed on different cells

Answer 73

T1R, T2R

Question 74

Taste afferent fibers traveling in CN VII, CN IX, and CN X synapse in their respective ganglia and then project via the __________ to synapse in the ________ in the ______________

Answer 74

solitary tract, rostral solitary nucleus (gustatory nucleus), rostral posterolateral medulla

Question 75

The ________ pathway is ipsilateral

Answer 75

gustatory

Question 76

Gustatory pathway: Neuron 1 has dendrites in the _______, cell body in the ______, ______, and ______ ganglia, axons in the _______ tract, and projects to the ________ nucleus directly adjacent to the vestibular nuclei and dorsal motor vagal nucleus.

Answer 76

taste buds, geniculate, petrosal, nodose, solitary tract, solitary nucleus

Question 77

Gustatory pathway: Neuron 2 has its cell body in the _______ nucleus, axon in the _______ tract in the _______ (CNS), and projects to the _________ of the thalamus

Answer 77

solitary nucleus, central tegmental tract, pons, ventral posteromedial nucleus of the thalamus

Question 78

The central tegmental tract when it is in the pons is located adjacent to the __________

Answer 78

medial lemniscus

Question 79

Gustatory pathway: Neuron 3 has its cell body in the _______ nucleus of the thalamus, axons in the ________, and projects to the _______, _________, and _________.

Answer 79

ventral posteromedial nucleus of the thalamus, posterior limb of the internal capsule, insula, frontal operculum, postcentral gyrus

Question 80

______ precedes the onset of Alzheimers, Parkinsons, and Huntingtons disease

Answer 80

smell disorder (anosmia)

Question 81

olfactory hallucinations are also referred to as _______

Answer 81

uncinate fits