CHEMICAL SENSES pt.2 Flashcards
In a study, Fox dropped a bag of PTC by accident and it went everywhere, what did he find from this
his collegue noted how bad it tasted but fox tasted nothing, he called this “taste blindness”
some peolple are considered supertasters because they find certain foods to be bitter and harsh, why might this be:?
due to the shape, number, and size of papillae, also genetics
What is Adaptation-produced Potentiation?
when adaptation to one taste increases sensitiviry to another
eg. adapting to a bitter substance will make sweet substances taste even sweeter (hard for salt bc saliva contains salt already)
what is the Artichoke effect?
after eating cooked artichoke, 60% of people found that water tastes sweat
What is so special about miracle fruit?
it contains glycoprotein miraculin , which makes sour foods (like lemon, lime, etc) taste sweat
What is Cross-adaptation
when exposure to one taste reduces your sensitivity to another (opposite of adaption produced potentiation)
What is “Chemesthesis”
sensations arising when chemical compounds in foods activate receptor mechanisms for pain, touchm or thermal perception
eg. tongue burning from a chilli pepper, coolness from mouthwash
Capsaicn (spicy heat) is mainly found in the white _____ inside chilli pepers, not the tip
membrane
what can capsaicn relieve?
arthritis pain by lowering levels of substance P
What is Menthol?
alcohol extracted from peppermint that produces a cool sensation, acts on thermoreceptors
Methol inhibits _____ of Ca2+ from cold receptor which causes depolarization, an increased firing of cold receptors
efflux
We can discriminate over 1 _____ olfactory stimuli
1 trillion
smell stimuli are __________ (molecules of volatile substances
odourants
According to Aristotle, what are the 4 basic categorys of odourants?
Pungent, succulent, acid, astringent
Henning created an odour prism, what were some of the odours?
Flowery, spicy, burnt, resinous, fruity, putrid
he beleived any odour was a combination of these properties (but most need more than just 6 categories)
What is the Stereochemical theory?
the idea that classification of odour is based on the shape of the molecule
what is anosmia
permanently never able to smell again (smell blindness)
molecules bind to what receptor>
Olfactory receptors (ORs) on the cilia of the Olfactory receptor neurons (ORN)
this opens ion channels in membrane
orns are replaced every 5-7 weeks
