Autumn.wmf (12088 bytes)Introduction to Organismal Biology (BIOL221) - Dr. S.G. Saupe; Biology Department, College of St. Benedict/St. John's University, Collegeville, MN 56321;;

Grasshopper Dude

The following diagram is a "Saupian" model for the ear. 

Diagram Labeling Label the diagram with each of the following structures:

  • Basilar membrane

  • cochlea

  • Cochlear duct (middle canal)

  • ear drum

  • Eustachian (auditory tube)

  • Hair cells

  • Incus (anvil)

  • Inner ear

  • Malleus (hammer)

  • Middle ear

  • Organ of Corti

  • Outer ear

  • Oval window

  • Pinna

  • Round window

  • Semicircular canals

  • Stapes (stirrups)

  • Tympanic canal

  • Tympanic membrane

  • Vestibular canal

  • Vestibular membrane


  1. Which structure (s) is involved in balance?

  2. Which structure is coiled like a snail?

  3. Which structure leads to the mouth?  Why?

  4. Which structure is especially prone to damage by loud sounds?

  5. If you have tubes in your ears, in which structure would you find them?  Why are they inserted?

Hearing "By-the-numbers"
Number the following events in sequence.  The first one is done for you.

_____ Initiate action potential _____ Sound perception
_____ Hair cells bend _____ Tympanic membrane vibrates
__1__ Sound wave _____ Incus
_____ Pressure waves in fluid of cochlea move from vestibular to tympanic canal _____ Oval window
_____ Stapes _____ Depolarization
_____ Hair cells from organ of Corti contact tectorial membrane _____ Brain
_____ Basilar membrane vibrates _____ Malleus


| Top| SGS Home | CSB/SJU Home | Biology Dept | Biol221 Home | Disclaimer |

Last updated: March 14, 2008        � Copyright by SG Saupe