Chapter 27, Problem 9SQ

Mr. Johnson is becoming slightly deaf. To test his hearing, his doctor holds a vibrating tuning fork tightly against the back of Mr. Johnson’s skull. This sends vibrations through the bones of the skull, setting the fluid in the cochlea in motion. Mr. Johnson can hear the tuning fork this way, but not when it is held away from his skull a few inches from his ear. Where is Mr. Johnson’s hearing problem located? (Explain your answer.)

1. a. in the auditory nerve leading to the brain
2. b. in the hair cells in the cochlea
3. c. in the bones of the middle ear
4. d. in the fluid of the cochlea