ANAT 101 Lecture Notes - Earwax, Tectorial Membrane, Crista Ampullaris

• School: Queen's University
• Department: Anatomy and Cell Biology
• Course: ANAT 101
• Professor: Richard Oko

Document Summary

Regions of the ear external/outer ear -> collects + directs sound waves middle ear -> amplifies sound waves internal/inner ear -> contains sensory organs for hearing and balance. External ear: directs waves towards tympanic membrane, lateral 1/3 of canal = cartilage, medial 2/3 = temporal bone. The middle ear: air-filled bony compartment with several key features. 3 bones (ossicles): vibrate to amplify sound waves. Openings (windows) to middle ear -> oval window, round window. Spiral shaped structure containing organ of corti (transduces sound waves into electrical impulses for brain) Made up of utricle and saccule -> detect gravity and linear acceleration. 3 canals (anterior, posterior, lateral) that detect complex rotational motion. Membranous labyrinth contains endolymph filling the sensory structures. Auditory system and cochlea: movement of stapes spread fluid waves through compartments of cochlea (from oval window to round, scala vestibuli, scala tympani window, 2 compartments (separated by cochlear duct) Organ of corti (aka spiral organ in cochlear duct)