1. The Special Senses Lesson 2:
The Senses of Hearing, Taste, Smell and Touch

2. Lesson Objectives
Upon completion of this lesson, students should be able to …
Describe the anatomy of the ear and briefly explain the function of each structure.

3. Lesson Objectives
Describe the anatomy of the nose and explain how the sense of smell occurs.
Identify the anatomical structures that make up the special senses.
Discuss the sense of taste, and briefly explain the function of taste buds.

4. Anatomy of the Ear 4

5. Three Main Divisions of the Ear
External ear
Middle ear
Inner ear 5

6. Label ear

7. Structure and Function of the External Ear
Pinna, or auricle:
Funnels sound waves
Auditory canal, or auditory meatus:
S-shaped, secretes cerumen

8. Structure and Function of the External Ear
Tympanic membrane, or eardrum:
Separates the external ear from the middle ear

9. Take a closer look:
Otoscope

10. Structure and Function of the Middle Ear
Contains : malleus (hammer), incus (anvil), stapes (stirrup)
Function
Transmits sound vibrations
Equalizes air pressure
Protects from damaging noise

11. Structure and Function of the Inner Ear
Bony labyrinth :
Cochlea, vestibule, and three semicircular canals
Cilia=Tiny hair cells

12. Structure and Function of the Inner Ear
Eustachian tube extends from the middle ear to the nasopharynx

13. Hearing test http://www.freehearingtest.com/test.shtml
Or use audiometer

14. Path of Sound Vibrations14

15. Two Most Common Types of Hearing Disorders
Conductive:
Hearing loss can be corrected
Sensorineural:
Hearing loss cannot be corrected

16. Four Types of Taste Cells
Sweet
Sour
Salty
Bitter

17. The Sense of Touch Oldest, most primitive sense
More nerve endings equals more sensitivity

18. Medical Specialists
Ears, nose and throat specialist