Olfactory system

Question 1

what are the components of the olfactory system

Answer 1

olfactory: mucosa, nerve, bulb, tracts, cortex

Question 2

where is the olfactory mucosa located

Answer 2

located in superior aspect of each nasal fossa (spenoethmoid recess), 2.5 cm square of specialized mucosa, extends onto the median nasal septum and lateral wall

Question 3

what type of epithelial cells line the olfactory mucosa

Answer 3

PSCC

Question 4

what are olfactory glands

Answer 4

bowman’s gland, found beneath epithelium, secretes fluid onto surface of mucosa to dissolve odorant chemicals

Question 5

what are olfactory cells

Answer 5

bipolar neurons that are modified to serve as olfactory receptor cells and conduct impulses, few month turnover, axons are unmyelineated (CN1)

Question 6

what are olfactory nerves

Answer 6

formed by axons of olfactory cells, bundles of axons enter cranial cavity through cribriform foramina of ethmoid bone, axons enter olfactory bulb and terminate in clusters of synaptic endings called glomeruli

Question 7

what are olfactory bulbs

Answer 7

extension of brain that is along ventral surface of frontal lobe, mitral cells, tufted cells

Question 8

what are mitral cells

Answer 8

dendrites arborize within glomeruli with olfactory cell axons, one mitral cell communicates with several olfactory cells, axons comprise most of fibers of olfactory tract and project centrally in brain

Question 9

what are tufted cells

Answer 9

another type of neuron found within olfactory bulbs, axons of these cells travel through olfactory tracts

Question 10

what are the association neurons of the olfactory bulb

Answer 10

include periglomerular cells, granule cells, serve to modify olfactory info before reaching the cerebral olfactory areas

Question 11

what is the olfactory tract

Answer 11

most fibers are from mitral cells, but some from tufted cells

Question 12

where do olfactory tract fibers lead to

Answer 12

olfactory trigone at base of brain, which splits into lateral olfactory stria and medial olfactory stria

Question 13

where do most of the olfactory tract transverse to

Answer 13

lateral olfactory stria to the lateral olfactory area of the cerebrum

Question 14

T/F some fibers make up an intermediate olfactory stria and terminate in the anterior perforated substance

Answer 14

true

Question 15

T/F although often observed as a ridge of tissue, the “medial olfactory stria” does not include olfactory tract fibers to the septal area as originally thought

Answer 15

true

Question 16

what are the cerebral olfactory areas

Answer 16

lateral olfactory area and anterior perforated substance

Question 17

what does the lateral olfactory area receive input from

Answer 17

the olfactory bulbs through fibers of the lateral olfactory stria

Question 18

what areas are included in the lateral olfactory area

Answer 18

uncus, limen insula, part of amygdala

Question 19

what areas comprise the primary olfactory area

Answer 19

uncus, limen insula, part of amygdala (largely in temporal lobe)

Question 20

what is the primary olfactory area responsible for?

Answer 20

subjective appreciation (awareness) of an olfactory stimulus

Question 21

what is the olfactory association area

Answer 21

cortical areas adjacent to the primary olfactory cortex: permits the identification of the qualities of odors and also the significance

Question 22

what do the lateral olfactory areas (with hippocampus & amygdala) serve as?

Answer 22

important limbic system structures–allow for odors to influence memories, emotions, and visceral responses

Question 23

where is the anterior perforated substance positioned

Answer 23

between lateral and medial olfactory stria, area forms intermediate olfactory area