L7 - Intro chemical senses Flashcards
What is the role of taste and smell?
Protect the body from harmful substances
prepare body for digestion
strongly connected to memory
How often do taste receptors regenerate?
every 1-2 weeks
How often do smell receptors regenerate?
ever 5-7 weeks
What are the functions of taste?
Identify necessary nutrients for survival
detects harmful substances
What compound produces a sour taste?
hydrochloric acid
What compound produces a salty taste?
sodium chloride
What produces a sweet taste?
sucrose
What produces a bitter taste?
quinine
What compound produces a umami taste?
Monosodium glutamate (MSG)
What’s the structure of the taste system?
Tongue papillae
Filiform - cone-shaped, no taste buds
Fungiform - mushroom-shaped, has taste buds
Foliate - folds, contains taste buds
Circumvallate - flat-mound shaped, has taste buds
taste buds - each contain 50-100 taste cells with tips protruding into the taste poor
where does transduction take place?
@ taste receptors
What is the taste system pathway?
nerve fibres from tongue to mouth synapse in the nucleus of the solitary tract
from there to the thalamus and then to the frontal operculum and insula
What are the differences in smell for humans and animals
Humans are microsatic (smell isn’t crucial for survival)
many animals are macrosmatic (smell is crucial for survival)
What is the brain pathway for smell?
olfactory bulb –> piriform cortex (primary olfactory cortex) –> orbitofrontal cortex –> amygdala (linked to emotion)
What are the components needed for flavour perception?
flavour = taste + smell
