Question

the sensation of loudness or the volume of a sound is detected by ________. a) vibration along a greater length of the basilar membrane, stimulating a greater number of hair cells b) greater movement of the basilar membrane resulting in greater deflection of the hair cells c) sounds that can travel all the way to the apex of the scala vestibule with enough energy remaining to deflect hair cells d) faster vibration of the basilar membrane resulting in a higher frequency of hair cell stimulation

Explanation:

Loudness is related to the amplitude of sound waves. When the amplitude is larger, it causes greater movement of the basilar membrane. This greater movement leads to a greater deflection of the hair cells. Hair cells are responsible for converting mechanical vibrations (from sound) into neural signals. A greater deflection of hair cells (due to more intense basilar membrane movement) is what leads to the perception of louder sound.

• Option A: Vibration along a greater length of the basilar membrane is more related to pitch (frequency - different regions of the basilar membrane respond to different frequencies), not loudness.
• Option C: Sounds traveling to the apex with energy is also more about frequency (lower - frequency sounds can reach the apex), not loudness.
• Option D: Faster vibration of the basilar membrane is related to higher frequency (pitch), not loudness.

Answer:

B. greater movement of the basilar membrane resulting in greater deflection of the hair cells