The Special SensesLesson 2:The Senses of Hearing, Taste, Smell and Touch

Lesson ObjectivesUpon completion of this lesson, students should be able to …

Describe the anatomy of the ear and briefly explain the function of each structure.

Lesson ObjectivesDescribe 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.

Anatomy of the Ear

Three Main Divisions of the Ear

External earMiddle earInner ear

Label ear

Structure and Function of the External EarPinna, or auricle:

Funnels sound waves

Auditory canal, or auditory meatus: S-shaped, secretes cerumen

Structure and Function of the External EarTympanic membrane, or eardrum: Separates the external ear from the middle ear

Take a closer look:Otoscope

Structure and Function of the Middle Ear Contains : malleus (hammer), incus (anvil), stapes (stirrup)

FunctionTransmits sound vibrations Equalizes air pressureProtects from damaging noise

Structure and Function of the Inner Ear

Bony labyrinth : Cochlea, vestibule, and three semicircular canals

Cilia=Tiny hair cells

Structure and Function of the Inner EarEustachian tube extends from the middle ear to the nasopharynx

Hearing testhttp://www.freehearingtest.com/test.shtml

Or use audiometer

Path of Sound Vibrations

Two Most Common Types of Hearing Disorders

Conductive: Hearing loss can be corrected

Sensorineural: Hearing loss cannot be corrected

Four Types of Taste CellsSweetSourSaltyBitter

The Sense of TouchOldest, most primitive sense

More nerve endings equals more sensitivity

Medical Specialists

Ears, nose and throat specialist