Module 1 The Nervous System

Self-Check

Study the lesson and then test how well you understand the concepts by doing this test. This self test reflects the kind of questions that you will encounter on the Diploma examination. The first 7 questions include both numerical response and multiple choice style questions. After doing these, you can autocheck to see how well you did.

Numerical Response Question

Use the following diagram to answer the next two questions.

Inquiry into Biology (Whitby, ON: McGraw-Hill Ryerson, 2007), 420, fig. 12.20. Reproduced by permission.

1. Match the following structures with those labeled on the picture of the human ear. Record the number from the diagram in the space that corresponds below. (Record all four digits of your answer in the spaces below.)
   
   __________              ___________           ___________           __________
   semicircular               tympanum                  middle ear               cochlea
   canals
2. The structure that is primarily responsible for maintaining dynamic equilibrium is represented by
   
   
   1. 1
   2. 2
   3. 3
   4. 4
3. Which pair gives an INCORRECT function for the structure(s)?
   
   
   1. Eustachian tube – equalization of pressure
   2. cochlea – initiation of nerve impulses
   3. round window – dissipation of pressure waves
   4. utricle and saccule – dynamic equilibrium
4. Place the following events in the correct sequence after the first event stated below: Record the four digits of your answer below.
   
   

   __________              ___________           ____________         __________

   First Event: Sound waves push against the tympanum.

   1. Tiny hair-like cells in the organ of Corti respond to vibrations by stimulating sensory fibres

   2. Vibrations are amplified by the ossicles.

   3. The basilar membrane begins to vibrate.

   4. The oval window receives vibrations from the ossicles

Use the following information to answer the next two questions.

A cochlear implant is very different from a hearing aid. Hearing aids amplify sound. A cochlear implant is designed to compensate for damaged or non-functional parts of the inner ear. When hearing is functioning normally, complex parts of the inner ear convert sound waves in the air into nerve impulses. These impulses are then sent to the brain, where they are interpreted and recognized as sound. A cochlear implant works in a similar manner. It electronically finds useful sounds and then sends impulses to the brain. Sounds heard through an implant may sound different than sounds heard without, but it enables many people to communicate orally in person and over the phone who would not be able to do so without such a device.

5. Identify the specific structure(s) of the inner ear that the cochlear implant is intended to replace.
   
   
   1. tympanic membrane
   2. hair cells located on the basilar membrane
   3. round window
   4. ossicles
6. Identify the specific structures of the ear that have the same function as a hearing aid.
   
   
   1. tympanic membrane and ossicles
   2. hair cells and sensory fibres on the basilar membrane
   3. round and oval windows
   4. vestibular apparatus
7. Which of the following statements is INCORRECT with respect to hearing in humans?
   
   
   1. The hair cells of the organ of Corti are able to distinguish both the frequency (pitch) and amplitude (loudness) of sound waves.
   2. The hair cells of the organ of Corti are able to detect sound within the frequency range of 0 Hz to 20 Hz.
   3. High frequency sounds most strongly stimulate the hair cells closest to the oval window.
   4. Low frequency sounds most strongly stimulate the hair cells farthest from the oval window.