External Ear

Question 1

Pinna

Answer 1

shape is determined by cartilage beneath it, helps to localize sound

Question 2

Lobule

Answer 2

no cartilage

Question 3

antihelix

Answer 3

splits into 2 crura, 2 crura in superior portion

Question 4

helix

Answer 4

outer rim

Question 5

concha

Answer 5

acoustic resonanting cavity

Question 6

tragus

Answer 6

provides some protection

Question 7

external auditory meatus

Answer 7

lateral 1/3 is cartilaginous: meatal skin is thick, sebaceous/cerminous glands secrete earwax

medial 2/3 is ossesous: meatal skin is thin and sensitive

Question 8

tympanic membrane

Answer 8

tympanic ring (bone)

fibrocartilaginous ring: eardrum rim attached to tympanic ring of temporal bone

mallear folds embedded between loose connective tissue of pars tensa and pars flaccida

Question 9

Pars Tensa

Answer 9

majority of TM, attached to tympanic ring, outer radiating parts of tissues, inner circular fibrous layer

Layers:

cutaneous: continuous with meatal skin
fibrous: radial and circular fibers only in tensa make TM internally stiff
mucousal: continuous with epithelial lining of whole middle cavity

Question 10

Pars Flaccida

Answer 10

umbo manurum

Layers:
cutaneous: continuous with meatal skin
mucosal layer: continuous with epithelial lining of whole middle cavity