Tape in Notebook 5 mins 50: 12.3 Clinical Application Smell and Taste Disorders 54: Lab 31 Smell and Taste Lab 55: Hearing Case Study: No More Loud Music (Read/Highlight/Questions) 56: External Ear Picture (color-coded--- Functions) 56: Now Hear This: Don’t Remove Earwax (Read/Highlight/Questions) 58: Middle Ear Picture (color-coded---Functions) 60: All About Ear Infections (ONLY Highlight) 62: Inner Ear Picture (color-coded---Functions)

12.5: Major Parts of the Inner Ear Sponge: Set up Cornell Notes on pg. 63 Topic: 12.5: Major Parts of the Inner Ear Essential Questions: Picture Bubble Map of Inner Ear: Cochlea Semicircular canals Osseous Labyrinth Membranous Labyrinth Vestibule Vestibulocochlear Nerve 12.5: Major Parts of the Inner Ear 2.1 Atoms, Ions, and Molecules QUIZ: On MONDAY Labeling the parts of the external, middle, and inner ear Extra Credit: IB Art Show @ mall Little Mermaid Tonight 6pm Sat 2pm

Inner Ear

Inner Ear

Inner Ear The Inner Ear is a complex system of labyrinths Osseous (bony) labyrinth rigid outer wall of inner ear secretes perilymph which conducts sound vibrations Membranous labyrinth tube within osseous labyrinth filled with endolymph which conducts sounds Houses receptor cells for hearing and equilibrium

Inner Ear Three Parts of Labyrinths: Semicircular canals 1. Cochlea (coke/le/ah) or (Kok/le/ah) functions in hearing 2. Semicircular canals provides a sense of equilibrium 3. Vestibule functions in equilibrium AND hearing Semicircular canals vestibule cochlea

The Vestibulocochlear Nerve: Aka acoustic or auditory nerve Has two branches: 1. vestibular branch: senses changes in the position of the head to maintain equilibrium 2. cochlear branch: send signals to brain where sound can be interpreted

Pg. 62 Cochlea Organ of Corti Scala Vestibuli Scala Tympani Leave a little room for info about cochlea Organ of Corti Scala Vestibuli Scala Tympani Cochlear Duct Vestibular Membrane Basilar Membrane

Cochlea Cochlea Functions in hearing Shaped like a snail Coiled around a bony core (modiolus)

Cochlea Scala vestibuli upper compartment of cochlea leads from oval window to apex of spiral conducts sound vibrations to the scala media (cochlear duct) contains perilymph Oval window

Cochlea Scala tympani lower compartment extends from apex of the cochlea to round window allows the vibrations to escape into the air of the tympanic cavity contains perilymph Round window

Cochlea Scala Vestibuli Scala Tympani Vestibular membrane separates cochlear duct from scala vestibuli Separates endo/perilymph Diffusion barrier- allows nutrients to travel from perilymph to endolymph Cochlear duct aka scala media lies between the scala vestibuli and scala tympani Filled with endolymph Houses the organ of Corti Basilar membrane separates cochlear duct from scala tympani Floor of cochlear duct Separates the endo/perilymph endolymph Scala Vestibuli Scala Tympani

Organ of Corti ***Organ of Corti***: Hair cells: hearing receptor cells located here on upper surface of basilar membrane Different frequencies of vibration move different parts of basilar membrane Sound frequencies cause hairs of receptor cells to bend Simulates the vestibulocochlear nerve which will send the signals to the brain for interpretation

Pg. 62 Label this diagram of the Ear *Quiz on Mon. Tympanic Membrane Cochlea Incus Tympanic Cavity Auricle Stapes Round Window Malleus Auditory Tube Semicircular Canals Vestibulocochlear Nerve External Acoustic Meatus

Pg. 62 Label this diagram of the Ear *Quiz on Mon. stapes Incus malleus Semicircular canals Auricle Tympanic membrane cochlea Vestibulocochlear nerve Round window External acoustic meatus Tympanic cavity Auditory tube Tympanic Membrane Cochlea Incus Tympanic Cavity Auricle Stapes Round Window Malleus Auditory Tube Semicircular Canals Vestibulocochlear Nerve External Acoustic Meatus

12.5: How Sound Travels Through the Inner Ear Sponge: Set up Cornell Notes on pg. 65 Topic: 12.5: How Sound Travels Through the Inner Ear Essential Questions: NONE. 12.5: How Sound Travels Through the Inner Ear 2.1 Atoms, Ions, and Molecules

Ear Labeling Quiz Time 15pts 13. 14. 15.

The stapes vibrations enter the perilymph at the oval window Travel along the scala vestibuli Enter the endolymph of the cochlear duct Move the basilar membrane a. Causing the hair cells in the Organ of Corti to bend b. Send signals along the vestibulocochlear nerve to the brain Vibrations enter the perilymph of the scala tympani Forces are dissipated into the air in the tympanic cavity DON’T WRITE

1. Sound waves vibrate the tympanic membrane 2. The tympanic membrane vibrates the auditory ossicles 3. The vibrations enter the perilymph (fluid in the scala vestibule and scala tympani) at the oval window 4. Travel along the scala vestibule (top compartment of cochlea) 5. Enter the endolymph (fluid in the cochlear duct) of the cochlear duct 6. These vibrations move the basilar membrane a. Frequencies cause organ of corti to bend against the tectorial membrane b. Vesicles in hair cells release neurotransmitters c. Neurotransmitters stimulates the ends of nearby sensory nerve fibers d. Impulse travels along the cochlear branch of the vestibulocochlear nerve e. To the medulla oblongata f. Through the midbrain g. To the thalamus h. Into auditory cortices of the temporal lobes of the cerebrum (BRAIN) where they are interpreted 7. Vibrations enter the perilymph of the scala tympani 8. Forces are dissipated into the air in the tympanic cavity by movement of the round window

Inner Ear Animation Video

Cochlear Implant Implant placed under skin above the ear Leads to electrodes placed near auditory nerve in the cochlea Wear a head set that has a microphone to pick up incoming sounds Sends electrical signals to cochlea Auditory nerve is stimulated

Cochlear Implants 3m7s

8 mo. Old Deaf Baby with Cochlear Implants 49s http://www.youtube.com/watch?v=HTzTt1VnHRM

Bionic Ears Start at (4m42s) 4m10s

Clinical Application 12.4: Getting a Cochlear Implant