ATI Pathophysiology Practice Exam

Which of the following structures located at the end of the ear canal vibrates when sound waves strike it?

1. Ossicles

2. Auditory tube

3. Tympanic membrane

4. Cochlea

The correct answer is: Tympanic membrane

The structure responsible for vibrating when sound waves strike it is the tympanic membrane, commonly known as the eardrum. This thin membrane separates the external ear from the middle ear and plays a crucial role in the auditory system. When sound waves enter the ear canal, they create pressure changes that cause the tympanic membrane to vibrate. These vibrations are then transmitted to the ossicles, which are small bones in the middle ear, amplifying the sound before it reaches the inner ear. The ossicles, while essential for hearing, do not directly vibrate in response to sound waves themselves; they instead respond to the vibrations initiated by the tympanic membrane. The auditory tube’s function is to equalize pressure between the middle ear and the environment, rather than to vibrate with sound. The cochlea, on the other hand, is part of the inner ear responsible for converting sound vibrations into neural signals, but it is not the structure that initially vibrates upon exposure to sound waves. Therefore, the tympanic membrane is the correct answer, as it is the first structure that responds to sound waves in the auditory pathway.