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Anatomy and Physiology of OUTER Ear

            ANATOMY AND PHYSIOLOGY OF OUTER EAR

Hearing is one of the major sense and is important for communication . The function of ear is to convert physical vibration into an encoded nervous impulse. The ears are praised organ , one on each side of the head with organ itself , which is technically the Temporal Bones. The conductive mechanism is divided into three parts , An OUTER EAR , MIDDLE AND INNER EAR .

OUTER EAR   

Outer ear is divided into two parts : PINNA and EXTERNAL AUDITORY CANAL

PINNA :

The Pinna is that part which protudes from the side of the skull made of cartilage covered by skin , collects sound and channels it into the ear sounds that comes from in front more than from behind and is helpful in localizing sounds.

FUNCTION OF PINNA :

  • The visible portion that is commonly refferedto as "the ear".
  • Help localize sound sources.
  • Each individual pinna creates a distinctive imprint on the acoustic wave travelling into the Auditory canal. 

EXTERNAL AUDITORY CANAL 

The ear canal is about 4cm long and consist of an Outer and inner part . The outer portion  is lined with Hairy skin containing sweat glands and oily SEBACEOUS glands wich together from ear wax.

FUNCTION OF EAR DRUM :

  • Protects the ear drum.
  • Resonator provides about 10dB of gain to the eardrum at around 3,300Hz (Hetz).

CERUMEN

THE PURPOSE OF WAX :

  • Repel water.
  • Trap dust , sand particles and other debris .
  • Cleanse ear canal.
  • Antibiotics , Antiviral , Antifungal properties.
  • Mosturize epithelium in ear canal.
  • Discourages insects.

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