Anatomy of Ear: Middle Ear

Middle ear muscles are innervated by 

a). Cranial nerve VII
b). Cranial nerve V
c). Cranial nerve VII and VIII
d). Cranial nerve VII and IX
e). Cranial nerve V and VII

Anatomy of Ear: Inner Ear

Name a motor protein found in cochlea.

a). Myosin

b). Prestin

c). Connexins

d). Innexins

e). Otoferlin

Anatomy of Ear: Inner Ear

Stereocilia of outer hair cell in cochlea projects into __________.


a). Basilar membrane
b). Reissner membrane
c). Tectorial membrane
d). Spiral ligament
e). None

Anatomy of Ear: Tympanic Membrane

The tympanic membrane is placed in the canal at an angle of _____ degrees with the floor.

a). 30

b). 45

c). 55

d).135

e).150

correct answer: c

Tympanic membrane is a thin semi-transparent membrane which separates middle ear from the external ear. It is made up of three layers of tissues, i.e. outer epithelial layer, middle fibrous layer and inner mucous layer. It is oval in shape and measures approximately 10 mm vertical plane and and 9 mm in horizontal plane. It is obliquely placed at the end of the ear canal at an angle of about 55° with the floor of the meatus.

Anatomy of Ear: Auricle

How many intrinsic muscles are found in the auricle _____?

a). three
b). nine
c). six
d). ten
e). four

correct answer: c

The intrinsic muscles of auricle are:

1. The Helicis major is a narrow vertical band located on the anterior margin of the helix. It arises from the spina helicis, and is inserted into the anterior border of the helix.

2. The Helicis minor is an oblique bundle and covers crus helicis.

3. The Tragicus is a short, flattened vertical band on the lateral surface of the tragus.

4. The Antitragicus from the outer part of the antitragus, and is inserted into the cauda helicis and antihelix.

5. The Transversus auriculae is placed on the cranial surface of the pinna. It consists of scattered fibers, extending from the eminentia conchæ to the prominence corresponding with the scapha.

6. The Obligus auriculae is found on the cranial surface, extending from the upper and back part of the concha to the convexity immediately above it.

Anatomy of Ear: Auricle

Extrinsic muscles of the auricle are _________, _________, and _________.

Answer:
Auricularis Anterior: It is thin and fan-shaped, and arises from the lateral edge of the epicranial aponeurosis, and project on the front of the helix.

Auricularis Posterior: It consists of two or three bundles, and arise from the mastoid portion of the temporal bone by short aponeurotic fibers and insert into the lower part of the cranial surface of the concha

Auricularis Superior: It is thin and fan-shaped, and arise from the epicranial aponeurosis, and converge the upper part of the cranial surface of the auricule.

Anatomy of Ear: Auricle

Auricle is predominantly made up of _______.

a). Elastic cartilage
b). Fibrocartilage
c). Muscle
d). Bone








correct answer: a

Anatomy of Ear: Auricle

Auricle is attached to the skull (from posterior) at an angle of ______ degrees.

a). 45
b). 30
c). 15
d). 90
e). 60







correct answer: b