CSD 3103





DUE: September 15, 2006




Multiple Choice


1.  Cerumen is produced in the


            a) entire external auditory canal

            b) cartilaginous external auditory canal

            c) osseous external auditory canal

            d) temporomandibular joint


2.  The portion of the tympanic membrane in which the malleus is

     embedded is the


            a) umbo

            b) annulus

            c) cone of light

            d) pars tensa


3.  The portion of the tympanic membrane that does not contain the

     fibrocartilaginous layer is the


            a) umbo

            b) pars tensa

            c) pars flaccida

            d) annulus


4.  The point of maximum retraction of the tympanic membrane is the


            a) annulus

            b) concha

            c) umbo

            d) pars flaccida


5.  The resonant frequency of the external auditory canal is


            a) 500-2000 Hz

            b) 3000-5000 Hz

            c) 8000-10,000 Hz

            d) 10,000-12,000 Hz



6.  The innermost layer of the tympanic membrane (the middle ear side)

      is covered with


            a) epidermis (skin)

            b) fibrous material

            c) mucous membrane

            d) muscle


7.  The cone of light of the tympanic membrane is


            a) a sign of pathology

            b) also referred to as the light reflex

            c) only seen in children

            d) caused by scar tissue


8.  The chain of bones in the middle ear is called the


            a) malleus

            b) incus

            c) stapes

            d) ossicles


9.  The manubrium is part of the


            a) malleus

            b) incus

            c) stapes

            d) eustachian tube


10.  The eustachian tube connects the middle ear with the


            a) outer ear

            b) inner ear

            c) nasopharynx

            d) nose






















Match the term from the box on the right with its definition.



_____ 1.

The largest of the ossicles, which is attacted to the tympanic membrane

a.  Aditus ad antrum

_____ 2.

The VIIth cranial nerve

b.  Crus

_____ 3.

The second bone in the ossicular chain that connects the malleus to the stapes

c.  Epitympanic recess

_____ 4.

The chain of three tiny bones in the middle ear

d.  Eustachian tube

_____ 5.

A space in the superior portion of the middle ear

e.  Facial nerve

_____ 6.

The Vth cranial nerve

f.  Incus

_____ 7.

A small muscle that can impede movement of the malleus

g.  Malleus

_____ 8.

The attic of the middle ear space

h.  Mucous membrane

_____ 9.

The moist lining of the middle ear space

i.  Ossicles

_____ 10.

In anatomy, a leg, as of the stapes

j.  Oval window

_____ 11.

A membrane separating the middle ear from the inner ear

k.  Round window


A channel connecting the middle ear to the nasopharynx

l.  Stapedius muscle

_____ 13.

The smallest of the ossicles, which stands in the oval window

m.  Stapes

_____ 14.

A membrane, supporting the footplate of the stapes, that separates the middle ear from the inner ear

n.  Tensor tympani muscle

_____ 15.

A small muscle, connected to the stapes that impedes movement of the ossicles when it is contracted

o.  Trigeminal nerve










Short Answer



5 pts.  1.  Describe all the ways you can think of that the outer ear protects the tympanic membrane.






















5 pts.  2.  The middle ear is often described as an impedance matcher between the outer ear and the inner ear.  Why is it necessary for the middle ear to do this??  What would happen if the middle ear wasn’t there and sounds entered the cochlea directly?




















5 pts.  3.  Describe the acoustic reflex.  What is the theoretical purpose of the reflex?