QuestionSBA
QuestionChoice
The stapedius muscle attaches to the stapes and is innervated by the facial nerve. This question asks about which muscle pulls on the malleus, not the stapes.
10023696
b
Stapedius
QuestionChoice
The tensor tympani pulls the handle of the malleus medially when contracting during the acoustic reflex. It is innervated by the tensor tympani nerve, which is a branch of the mandibular nerve. The acoustic reflex is when the muscles of the inner ear contract in response to loud noise, inhibiting the vibrations of the auditory ossicles and reducing the transmission of sound to the inner ear.
10023695
a
Tensor tympani
QuestionChoice
The membranous labyrinth lies within the bony labyrinth of the inner ear. It consists of the cochlear duct, semi-circular ducts, utricle and saccule. The cochlear duct is an organ of hearing and the semi-circular ducts, utricle and saccule are organs of balance. They play no role in the acoustic reflex.
10023699
e
Membranous labyrinth
QuestionChoice
The pars tensa is part of the tympanic membrane but is not a muscle. It may play some role in the acoustic reflex but it does not contract (as it is not a muscle) to pull the malleus medially.
10023697
c
Pars tensa
QuestionChoice
The tragus is located anterior to the beginning of the external acoustic meatus. It is an elevation of cartilaginous tissue and plays no part in the acoustic reflex.
10023698
d
Tragus
Concept
Chapter
2693
4112
Middle ear anatomy
Topic
138
Ear, Nose & Throat
17137
A 37-year-old male is at a football game when his team scores a goal. The noise level increases dramatically as everyone celebrates. The man's acoustic reflex helps protect his ears from the damage of the loud noises surrounding him.

In the acoustic reflex, which muscle contracts and pulls the malleus medially?
a