Sponge: Set up Cornell Notes on pg. 59 Topic: 12.6: Major Parts of the Inner Ear Essential Questions: None. 2.1 Atoms, Ions, and Molecules 12.6: Major Parts of the Inner Ear QUIZ: On MONDAY Labeling the parts of the external, middle, and inner ear

2 Inner Ear

3 The Inner Ear is a complex system of labyrinths (mazes)

Three Parts of Labyrinths: 1.Cochlea (coke/le/ah) functions in hearing 2. Semicircular canals Provides a sense of equilibrium 3. Vestibule (Vest-ib-ule) Functions in equilibrium AND hearing cochlea semicircular canals vestibule Inner Ear

5 Osseous (bony) labyrinth is the rigid outer wall of inner ear Divided into upper and lower compartments Secretes perilymph: High in sodium/calcium and low in potassium Cushion for membranous labyrinth Conducts sounds waves Inner Ear

6 Membranous labyrinth is a tube within the osseous labyrinth Houses the organ of Corti Filled with endolymph: High in potassium/calcium low in sodium Supports hair cells in sending signals to CNS Plays a direct role in hearing and balance Conducts sound vibrations

7 Inner Ear- Injury What if the perilymph and endolymph mix??? Injury or infection could cause one or both of the membranes to break If the membranes break, the fluid may mix causes damage to the hair cells Symptoms: Pressure in inner ear Vertigo Ringing in ears

8 The Vestibulocochlear Nerve (VIII): 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 Inner Ear

9 Cochlea Functions in hearing by translating sound into nerve impulses to be sent to the brain Shaped like a snail Coiled around a bony core (modiolus) Inner Ear- Cochlea Cochlea

How sound waves travel through cochlea 10

11 How sound waves travel through cochlea HighLow

12 Label, color code, and write a short description of each part of the cochlea 8 colors Inner Ear- Cochlea Direction that sound waves travel

13 Scala vestibuli (scale-ă vest-ib-uli) aka Reissner’s membrane Upper compartment of cochlear osseous labyrinth Oval window  apex (tip) of spiral Conducts sound vibrations to the cochlear duct Secretes perilymph Inner Ear- Cochlea Apex

14 Scala tympani (Scale-ă tymp-ă-nee) Lower compartment of cochlear osseous labyrinth Apex  round window Allows the vibrations to escape into the air of the tympanic cavity Contains perilymph Inner Ear- Cochlea Apex

15 Vestibular membrane Separates cochlear duct from scala vestibule Separates endolymph and perilymph BUT has a diffusion barrier which allows nutrients to cross through both fluids Inner Ear- Cochlea

16 Cochlear duct aka scala media Lies between the scala vestibuli and scala tympani Filled with endolymph Houses the organ of Corti Inner Ear- Cochlea

17 Basilar membrane (baz-i-lar) Separates cochlear duct from scala tympani Floor of cochlear duct Base for the sensory cells of hearing, the hair cells Inner Ear- Cochlea

18 Inner Ear- Cochlea Tectorial membrane Passes like a roof over the organ of Corti and bends the receptor hairs

19 Organ of Corti Main organ of hearing Contains 16,000 hair cells which when bent will release neurotransmitters Extends entire cochlea Inner Ear- Cochlea

Inner and Outer hair cells deal with volume 20

21 Inner Ear- Cochlea Vestibulocochler nerve Sparks a nerve impulse to be sent through to the brain

22 Inner Ear- Cochlea

23 Inner Ear- Cochlea Direction of vibrations once in inner ear: Oval window  Scala vestibuli  through Vestibular membrane  into Cochlear duct  vibrates the Basilar membrane  Organ of Corti [hair cells] release neurotransmitters  Nerve impulse stimulated  Vestibulocochlar nerve sends signals to brain  vibrations continue to Scala tympani  out of round window  to tympanic cavity

Transmission of sound to inner ear 24

25 Tympanic MembraneCochlea IncusTympanic Cavity Auricle Stapes Round WindowMalleusAuditory Tube Semicircular Canals Vestibulocochlear Nerve External Acoustic Meatus Inner ear Middle earExternal ear Label this diagram of the Ear *Quiz on Mon

26 Tympanic MembraneCochlea IncusTympanic Cavity Auricle Stapes Round WindowMalleusAuditory Tube Semicircular Canals Vestibulocochlear Nerve External Acoustic Meatus Auricle Incus malleus Tympanic membrane stapes Semicircular canals cochlea Vestibulocochlear nerve Round window Tympanic cavity Auditory tube External acoustic meatus Outer ear Middle ear Inner ear

27 QUIZ TODAY Only pencil All bags/backpacks/ CELLPHONES to back/front/side of room

Sponge: Set up Cornell Notes on pg. 61 Topic: 12.6: How Sound Travels Through the Inner Ear Essential Questions: None. 2.1 Atoms, Ions, and Molecules 12.6: How Sound Travels Through the Inner Ear QUIZ TODAY

P. 60 Crash course: Hearing Video Notes x10 Summary of Meniere’s Disease Causes: Symptoms: Treatment:

How Hearing Works 1m43s 30

How sound waves travel through cochlea 31

32 How sound waves travel through cochlea HighLow

How Sound Travels through the ear Make a flow map identifying the pathway that sound waves/vibrations travel through the ear 33 Include all 3 parts of the ear discussed in class (external/middle/inner) Include each part of the ear Include the pathway from the auditory nerve to the brain Must include pictures Turned into Google Classroom by 4/8 end of period Use notes/text/internet to support P for inner ear 462 for pathway through brain

34 Popplet can help you with organizing information. Helps you think visually and to see new connections between ideas and concepts. Color coding your popples can be a great way to add another concept level to your idea-gathering and is an excellent technique for organizing and remembering information.

35 You can add pictures from your computer You can draw your own pictures OR Use triangle in corner to resize as desired

36 To add new boxes: 1.Click the box you want to connect to 2.Grab gray circle 3.Drag and drop 4.A new box appears

Style: Flow Map 37

38 Style: Picture Bubble Map

REMEMBER TO… Log in using your school ID NOT as GUEST –Guest isn’t linked to your Google classroom account 39

Make a flow map identifying the pathway that sound waves/vibrations travel through the ear 40 P for inner ear 462 for pathway through brain Auricle  External acoustic meatus  Tympanic membrane  Malleus  Incus  Stapes  Oval window  Scala vestibuli  Cochlear duct  basilar membrane  organ of Corti  vestibulocochlear Nerve  pathway to brain Scala tympani  Round window Include an offshoot of the vibrations through the cochlear duct (p.459) and to the brain (p. 462)

Export to Google Classroom 1.Click Settings button 2.Export  Hi res png 3.Save to your Google Drive  Classroom  Anatomy 4.In a separate tab, go into Google Classroom 5.Open your classroom 6.Click assignment “Map of Sound/Vibrations through Ear” 7. Add  Google Drive  Classroom  Anatomy drive 8.Drag file 9.Click Turn in –Confirm submission 41

DON’T WRITE Sound waves enter the auricle  Funneled through the external acoustic meatus

1. Sound waves vibrate the tympanic membrane 2. The tympanic membrane vibrates the auditory ossicles (Malleus  Incus  Stapes)

3. The vibrations enter the perilymph of the scala vestibuli at the oval window

4. Vibrations travel along the scala vestibuli 5. Enter the endolymph of the cochlear duct

6. These vibrations move the basilar membrane

6. a. Vibrations 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 

6. e. Nerve impulse travels through the medulla oblongata  f. Through the midbrain  g. To the thalamus  h. Into the auditory cortex of the cerebral temporal lobes 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

Crash Course: Hearing 7m36s bullets top ½ p. 60

Meniere’s Disease Reading [Min-yair: French] Read/Highlight article on Meniere’s Disease Summarize: Cause/Symptoms/Treatment on bottom ½ p. 60