Taste and smell Flashcards
where are taste buds found
tongue, palate, tonsillar pillars, epiglottis and proximal oesophagus
where are circumvallate papillae found
posterior of tongue in a v shape
taste buds are found on these papillae
where are fungiform papillae found
anterior surface of the tongue
where are foliate papillae found
lateral margins
where are taste buds found on the papillae
embedded on the sides of the papillae
what chemicals can be tasted by taste buds
potassium sodium chloride adenosine inosine sweet bitter glutamate H+
what causes sour taste
H+
what causes salty taste
Na and K ions
what causes sweet taste
sugar and other similar chemicals - glycols, alcohols, ketones and others
what causes bitter tastts
many chemicals including alkaloids found in toxic plants
what causes umami taste
L glutamate
how do taste buds work
contain receptors which depolarise taste cells by either an ionotropic or metabotropic pathway
what are the relative taste thresholds for various tastes
bitter has the lowest threshold as it most commonly associated with dangerous substances so sensitivity must be high
sour is next lowest
then sweet and then salty
what is the taste pathway to the cortex
solitary nucleus, then thalamus, then insula and anterior operculum
where do the limbic components of taste go
via the thalamus
can activate brainstem nuclei for salivation or vomiting
