Which of the following structures in the ear is responsible for transmitting sound vibrations to the auditory nerve?

Step 1: Analyze the question The question asks which structure transmits sound vibrations to the auditory nerve. This is the last step in hearing, where vibrations become nerve signals.

Step 2: The concept: how sound travels through the ear

1. Auditory canal (outer ear): channels sound waves to the eardrum.
2. Eardrum (tympanic membrane): vibrates when sound waves hit it.
3. Ossicles (malleus, incus, stapes) in the middle ear: pick up and amplify the vibrations, passing them to the oval window.
4. Cochlea (inner ear): the fluid inside vibrates, and this stimulates the hair cells (organ of Corti). The hair cells convert the vibrations into nerve impulses.
5. Auditory nerve: carries the impulses to the brain, where they are interpreted as sound.

Step 3: Evaluate the options

• A. Eardrum: only receives sound waves and starts the vibrations.
• B. Ossicles: transmit and amplify vibrations to the cochlea, not to the nerve.
• C. Cochlea: contains the sensory hair cells that pass the signal to the auditory nerve. ✔
• D. Auditory canal: just a passage for sound waves.

Step 4: Answer The cochlea is the structure directly connected to the auditory nerve, so the correct answer is C. Cochlea.

Exam tip: Remember the order "Can Every Operation Create Noise?" (Canal → Eardrum → Ossicles → Cochlea → Nerve). The structure right before the nerve is the cochlea. Also, when a question mentions the nerve, think of the structure with sensory receptor cells, which is the cochlea for hearing.