International Licensing Examination (ILE) Practice Test

How does the inner ear also function as a transducer?

1. Transforms sound waves into vibrations

2. Converts mechanical energy to hydraulic energy

3. Amplifies electrical signals

4. Filters background noise

The correct answer is: Converts mechanical energy to hydraulic energy

The inner ear operates as a transducer primarily by converting mechanical energy into hydraulic energy. This process is critical for the function of hearing, as it allows for the effective transmission of sound. When sound waves enter the ear, they cause the eardrum to vibrate. These vibrations are then transmitted through the bones of the middle ear (the ossicles) to the oval window, which is the membrane leading into the cochlea of the inner ear. Once the vibrations reach the cochlea, they create waves in the fluid that fills this spiral-shaped structure. The movement of this fluid is what the inner ear accomplishes by converting the initial mechanical energy from sound waves into hydraulic energy. This hydraulic flow is essential for stimulating the hair cells located in the cochlea, which then convert these mechanical fluid movements into electrical signals sent to the brain. The other options focus on different functions that are not applicable to the role of the inner ear in sound transduction. For example, while amplification of electrical signals is important in hearing, it primarily occurs later in the auditory pathway rather than at the level of the inner ear. Additionally, transforming sound waves into vibrations occurs initially in the outer and middle ear, not in the inner ear. Filtering background noise is typically a function