CHEMICAL SENSES Flashcards
What is flavour?
a combination of smell and taste, can also include texture
its difficult to idenfity foods without _______.
Olflaction (smell)
Why was gustation adapted by humans?
to test if food is edible, spoiled, or poisonous
Why is salty important
to maintain elecrtolyt balance, cation (positivly charged ion in sla) is important
What ion does sour foods release
H+ ion
How us Umami created?
isolating glutamic acid and amino acid from seawead
The toung is covered with bumps called ______
papillae
Taste buds are found on papillae, what are the three types of taste buds
fungiform - mushroom shapes, found on tip and sides
Foliate - on the sides of tongue
circumvallate - back of tongue, surrounded by a trench
how many buds do we have, and what do they contain?
10,000 ; taste cells
taste buds wear out and are replaced how often?
every 7-10 days, less frequently replaced after age 45
sour substances contain H+ which ______ ion channels.
sodium penetrates the membrane of receptor which._________ it.
blocks’ depolarizes
What is Labeled-line coding
when each sensory neuron (or line) is dedicated to transmitting only one specific type of information (like a particular taste, sound frequency, or touch location) to the brain.
What is Population coding (across-fibre pattern)
there are no specialized receptors for each taste, taste is signaled by a pattern of activity across fibers
nerve fibers from front/sides of tongue project to the _______ _______ nerve
Chorda tympani nerve
fibers from back of tongue make uo part of the ________________ nerve
glossopharyngeal nerve.
fibers from mouth and throat project via the _____ nerve
vagus nerve
fibers from the soft palate project via superficial _________ nerve
petrosal
all the nerves from the mouth connect to what
nucleus of the solitary tract in medulla
what part of the tongue has no taste buds
the center
our tongue has the most sensitivity to what temperatures?
22-40c (why we enjoy hot coffee rather than room temp)
