12.5: Hearing: External Ear Sponge: Set up Cornell Notes on pg. 53 Topic: 12.5: Hearing: External Ear Essential Questions: What is the major function of the cerumen? 12.5: Hearing: External Ear 2.1 Atoms, Ions, and Molecules

REVIEW: Special Senses Location of special senses? Sensory receptors are within large, complex sensory organs in the head Hearing in ears------>hair cells

Overview of the Ear and Hearing 1m44s P. 52 Video notes 1-3 bullets http://www.youtube.com/watch?v=pCCcFDoyBxM

Hearing Ear – organ of hearing Three Sections External Middle Inner

Sound Waves and Our Ears (3m 28s) P. 52 Video notes 3-5 bullets

External Ear The external ear consists of all of the structures that face the outside Auricle (oar-i-cle) Funnel like structure Collects sounds waves traveling through the air Directs them into the external acoustic meatus (me-a-tus)

External acoustic meatus (me-a-tus) aka “ear canal” Passes into temporal bone Carries sound to tympanic membrane (ear drum) Lined with ceruminous (ser-room-inous) glands which secrete wax Protects, lubricates and cleans the ear Hairs guard the tube Hair and wax keep large foreign objects, such as bugs, out of the ear A tickling on the ear drum

CAUTION!!!!!

Cerumen Impaction 3m6s P. 52 Video notes 3-5 bullets http://www.youtube.com/watch?v=kq0Uudx3qF4

Otitis Externa “Outer Ear Infection” Otitis Externa aka “Outer ear infection” aka “Swimmer’s Ear” Inflammation of the outer ear and ear canal Swells and becomes tender to the touch Can be caused by bacteria or fungus Ear Canal almost swollen shut

Otitis Externa “Outer Ear Infection”

Tympanic membrane aka ear drum Vibrates in response to sound waves Reproduces the vibrations of the sound-wave source

The Outer and Middle Ear (3m28s) P. 52 Video notes 3-5 bullets

Color code each of the 3 parts (include key)

Now Hear This: Don’t Remove Earwax Reading Read/Highlight/ Answer Questions Class Discussion

Pg. 52 On pg. 52 Create Picture Bubble Map Color code to match notes Add the FUNCTION to each label