Which boundary marks separation between outer ear and middle ear?

Which boundary marks separation between outer ear and middle ear?

• A. Tympanic Membrane
• B. Outer Ear
• C. Pinna
• D. Eustachian Tube

Answer: (A)

The boundary between the outer ear and the middle ear is the tympanic membrane, the thin structure you hear called the eardrum. It sits at the end of the ear canal and vibrates in response to sound waves, passing those vibrations into the middle ear where the three tiny bones (ossicles) amplify and transfer them onward to the inner ear. The outer ear includes the pinna and ear canal, while the Eustachian tube connects the middle ear to the throat to equalize pressure; neither marks the boundary between outer and middle ear.

The boundary between the outer ear and the middle ear is the tympanic membrane, the thin structure you hear called the eardrum. It sits at the end of the ear canal and vibrates in response to sound waves, passing those vibrations into the middle ear where the three tiny bones (ossicles) amplify and transfer them onward to the inner ear. The outer ear includes the pinna and ear canal, while the Eustachian tube connects the middle ear to the throat to equalize pressure; neither marks the boundary between outer and middle ear.