BIO304H5 Lecture : #19 Hearing
Document Summary
1. large eardrumb to oval window: mechanical advantage: mechanical movement against water is more effective that air. Allow vibration from the ear to the chochlea. Hearing sound is mechanical vibrations of the air. Made up for by amplification vibrations on water. Organ corti: basic sensory strucutre that translate sound waves to electrical activities. Perilymph normal extracellular fluid we ve talked about all year. Opposite of the usual (we ll see its importance later . The whole thing is the organ of corti. As the the fluid is vibrated by the oval window from the mechanical movements of the middle ear causes the basilar membrane to vibrate. Which causes the movements of the tectorial membrane (movement like a windshield wiper) Tip link connected to the gate on the shorter cilia. Mechanical activation bent to the right opens the physically gated ion channel, thus allowing k+ ions into the cell (positive ions flow in) This is the change from mechanical to electrical.
