Olfaction and taste

Question 1

the three cell types in the nasal cavity are:

Answer 1

basal cells: replenish receptor cells
support cells: apical surface w/microvilli; support and nourish receptor cells
receptor cells: soma w/dendrite projecting to epithelial surface. unmyelinated fascicles join, became ensheathed by Schwann cells and form CN1.

Question 2

what is contained in the olfactory bulb:

Answer 2

glomeruli; termination of receptor cell axons and mitral cell dendrites (which project to other areas of the brain)

Question 3

increased sensitivity to smell in other species corresponds to:

Answer 3

increased NUMBER of receptor cells

Question 4

what is the signaling mechanism of odors?

Answer 4

Some have G protein coupled receptors&raquo_space; adenylate cyclase and cAMP. Others induce phospholipase C&raquo_space; breakdown membrane and produce IP3

Question 5

an individual glomerulus is innervated by:

Answer 5

axons from a single receptor type

Question 6

cortical processing:

Answer 6

allows multiple, individual scents to be processed as one scent. receives information from multiple glomeruli

Question 7

information from mitral cells sent to:

Answer 7

olfactory tract&raquo_space; piriform complex&raquo_space; entorhinal cortex. does not necessarily go through thalamus

Question 8

olfactory information projected to the amygdala allows for:

Answer 8

emotional and motivational aspects associated with odor

Question 9

olfactory information projected to the thalamus to the frontal lobe of the cortex allows for:

Answer 9

perception and discrimination of odors

Question 10

olfactory information projected to the entorhinal complex to the hippocampus allows for:

Answer 10

creating memories associated with odors

Question 11

what is the locus ceruleus:

Answer 11

increases olfactory sensitivity in emotional state; like increased sensitivity to food when hungry

Question 12

4 types of papillae on tongue:

Answer 12

fungiform, circumvillate, filiform, and foliate. Circumvillate contain half of the ~2000 - 5000 taste receptors.

Question 13

what is the difference between olfactory sensory receptor cells and taste buds?

Answer 13

taste buds = secondary sensory cells; do not have axons that convey information. nerve endings from facial, glossopharyngeal and vagus nerves innervate them.