Answer to Question 1
A
Answer to Question 2
The tympanic membrane, commonly called the eardrum, separates the middle and outer ears. This structure is slightly oval and is around 10 mm in diameter in the superior-inferior dimension. It is approximately 9 mm in diameter in the anterior-posterior dimension. The perimeter of the membrane is a fibrocartilaginous ring that fits into a groove in the temporal bone that is called the tympanic sulcus.
The tympanic membrane is composed of three layers of tissue: the outer, intermediate, and inner layers. The outer (cuticular) layer is continuous with the epithelial lining of the external auditory meatus (EAM) and the pinna. The intermediate (fibrous) layer is composed of a superficial layer of fiber and a deep layer of fiber. The inner (mucous) layer is continuous with the mucosa of the middle ear.
