Lecture 11: Gustatory and Olfactory Systems Flashcards
The three types of papillae
vallate
foliate
fungiform
Vallate
papillae # and # of taste buds for each
papillae = 8-9
250 taste buds each
Foliate
papillae # and
total # of taste buds on each side
papillae = 20 each side
100-150 taste buds each side
Fungiform
papillae # and
# of taste buds for each
papillae = 200-300
3-5 taste buds each
What is the normal variation in the number of taste buds for each person that accounts for the different thresholds for taste?
100 fold variation
Where can the 4 basic tastes be found on the tounge?
Can be percieved at any spot on the tongue where there are taste receptors
Where else can taste receptors be found and why?
The palate and pharynx
Involved in swallowing and reflex responses to good or bad tastes
What cranial nerves, name and number, innervate the taste receptors?
CN VII; facial
CN IX; glossopharyngeal
CN X; vagus
Where do the CN that innervate taste buds report to?
The Nucleus of the solitary tract
What does the structure of the sweet and bitter taste receptors allow for?
Amplification of the stimulus
What does increasing intracellular Calcium and causing vesicles of ntx to be released onto gustatory nerve describe?
Amplification
What all consists of the Central Gustatory Pathway?
CN 7, 9, 10
Solitary Nucleus & Tract on insula
Ventral Posteromedial Nucleus of the Thalamus (VPM)
How large of an area do olfactory epithelium take up
5 cm^2
How many olfactory neurons are there roughly?
several million
Why are the olfactory neurons unique?
Life span + Cilia
30-60 day lifespan and are replaced by basal cells
Cilia specialized for odor detection by binding dissolved oderants in a mucus layer
