1. March 25 th, 2010 Objective: Review the workings of the nose, tongue, and ear. –Coloring –Notes Do Now – get markers and start coloring!

2. Things to color Auricle / pinna External auditory meatus (canal) Tympanic membrane Malleus/incus/stapes (aka hammer/anvil/stirrup) (labeled on pic ) semicircular canal, vestibular nerve Cochlea (& round window) Auditory tubes Vestibule Oval window Basilar membrane Organ of corti Inner hair cells Outer hair cells Cochlear nerve fibers

3. The Ear Slide 8.20 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Houses two senses  Hearing  Equilibrium (balance)

4. Anatomy of the Ear Slide 8.21 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  The ear is divided into three areas  Outer (external) ear  Middle ear  Inner ear Figure 8.12

5. The External Ear Slide 8.22 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Involved in hearing only  Structures of the external ear  Pinna (auricle)  External auditory canal Figure 8.12

6. The External Auditory Canal Slide 8.23 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Narrow chamber in the temporal bone  Lined with skin  Ceruminous (wax) glands are present  Ends at the tympanic membrane (eardrum)

7. The Middle Ear or Tympanic Cavity Slide 8.24a Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Air-filled cavity within the temporal bone  Only involved in the sense of hearing

8. The Middle Ear or Tympanic Cavity Slide 8.24b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Two tubes are associated with the inner ear  The opening from the auditory canal is covered by the tympanic membrane  The auditory tube connecting the middle ear with the throat  Allows for equalizing pressure during yawning or swallowing  This tube is otherwise collapsed

9. Bones of the Tympanic Cavity Slide 8.25a Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Three bones span the cavity  Malleus (hammer)  Incus (anvil)  Stapes (stirrip) Figure 8.12

10. Bones of the Tympanic Cavity Slide 8.25b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Vibrations from eardrum move the malleus  These bones transfer sound to the inner ear Figure 8.12

11. Inner Ear or Bony Labyrinth Slide 8.26a Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Includes sense organs for hearing and balance  Filled with perilymph Figure 8.12

12. Inner Ear or Bony Labrynth Slide 8.26b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  A maze of bony chambers within the temporal bone  Cochlea  Vestibule  Semicircular canals Figure 8.12

13. Organs of Hearing Slide 8.27a Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Organ of Corti  Located within the cochlea  Receptors = hair cells on the basilar membrane  Gel-like tectorial membrane is capable of bending hair cells  Cochlear nerve attached to hair cells transmits nerve impulses to auditory cortex on temporal lobe

14. Organs of Hearing Slide 8.27b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure 8.13

15. Mechanisms of Hearing Slide 8.28 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Vibrations from sound waves move tectorial membrane  Hair cells are bent by the membrane  An action potential starts in the cochlear nerve  Continued stimulation can lead to adaptation

16. Mechanisms of Hearing Slide 8.29 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure 8.14

17. Organs of Equilibrium Slide 8.30a Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Receptor cells are in two structures  Vestibule  Semicircular canals Figure 8.16a, b

18. Organs of Equilibrium Slide 8.30b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Equilibrium has two functional parts  Static equilibrium – sense of gravity at rest  Dynamic equilibrium – angular and rotary head movements Figure 8.16a, b

19. Function of Maculae Slide 8.32 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure 8.15

20. The End Of the ear Now to some games!