HMB200H1 Lecture Notes - Lecture 10: Melanopsin, Olfactory Bulb, Neocortex
Document Summary
Lecture 10: taste and smell. Within the hindbrain is the solitary. Taste sensations fast sensations that are immediately stimulating the tongue ionotropic receptors that respond to salt and sour. Sodium ions are dissolved in water (nacl) Salt ions enter taste buds. Presence of salt ions produces a sensation of saltiness. Very fast, happens by quick ionotropic entering of sodium ions and depolarization of the taste buds. Sour: h+ ions block k+ channels. Very fast sensation of sour. H+ ions separates, and hydrogen acids (sour taste) results in the release of hydrogen ions in fluids. These hydrogen ions then block potassium channels = excitation. Blocking k+ channels = depolarization. Sweet: sugars activate g- protein coupled receptors, t1r2/t1r3 dimers. Produce the taste by way of the sweet receptors have sugars broken down into simple sugars. This then activates the gpcr sweet receptors produces a slower, but still quick sensation of sweet. Bitter: many g- coupled receptors for proteins t2r family.
