Structure
of EAR : External ear
•The ear consists of three parts namely, external , middle and internal ear.
•The external ear is formed by two parts :
1.Auricle or pinna
2.External auditory meatus
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•In many animals, the auricle can be moved and turned to locate the source of sound or, the auricle can be folded to avoid unwanted sound.
•But in human, the muscle moving the pinna are rudimentary and the movement is not possible.
•The external auditory meatus is slightly curved canal with a length 25 mm. It is divided into two parts:
a. Outer cartilaginous part
b. Inner bony part
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