The Outer Ear Comprises Of The Outer Flap

                                         The mammalian ear

   structure

The ear consists of 3 distinct parts

-         Outer ear

-         Middle ear

-         Inner ear

The outer ear comprises of the outer flap-like. Pinna which leads into the ear canal

·        Ear canal or external auditory meatus

·        The ear drum or tympanic membrane

The pinna is made of soft cartilages that tin answer to audio waves yesteryear vibration.

Functions:

The pinna collect audio waves too straight them along the ear canal where they concentrate on the ear drum.

The ear canal contains wax fine hairs which protect the ear from microbes too dust particles. The ear drum initiates vibration of the ossicles

Models:

The model ear is an air filled bedroom consisting of

-         Ossicles [hammer or malleus

    [ incus or anvil

    [ stirrup / stapes

-         Eustachian subway

Function:

The ossicles transmit too amplify audio waves to the inner ear.

The Eustachian subway links the midpoint ear to the pharynx. It helps to equalize air clitoris per unit of measurement area on the two side of the ear

Inner Ear:

The inner ear is a fluid filled chamber. It is made upwardly

-         Semicircular canals

-         Cochlear

-         Sacculus

-         Utriculus

The semi circular canals are 3 structures lying at correct angle to each other. Each i is swollen at i limb to shape an ampulla. The ampulla contains a cupula which houses sensory hairs. These hairs are sensitive to changes inward the displace too rotator of the head. The base of operations of the canals are swollen to shape a utriculus too sacculus where numerous sensory hairs are contained inward a gelatinous volume inside this volume are crystals of CaCo₃ called Otoliths

Functions: it is the construction for maintaining of balance. The cochlea is coiled too is the organ of hearing. In a cross section, it consist of 3 parallel canals

-         Vestibular  canal

-         Cochlea canal

-         Tympanic canal

These canal are separated yesteryear membranes inside the cochlear canal are sensory pilus cells which shape the organ of corti. The inner ear is filled amongst a fluid called perilymph wile the semicircular canal too the cochlea are filled amongst an internal fluid called endolymph. The diagram below shows the organization of these structures.

Step 2: Mechanism hearing

-         Sound waves reaching the pinna drive the vibration of the cartilages on the pinna.

-         The pinna directs the audio waves collected through the ear canal to the ear drum.

-         This causes the vibration of the tympanic fluids

-         The vibration of the fluid reaches the ossicle which amplifies the audio too passes it to the inner ear through the oval window.

-         The vibration of the oval window sets upwardly a vibration of the perilymph

-         This inward plow ready the endolymph vibration.

-         The vibration endolymph stimulates the pilus cells of the cochlea called the organ of corti.

-         The organ of cort1 generates a sensory impulse carried through the cochlea part of the auditory nervus to the brain

-         The encephalon hence interprets the moving ridge equally sound

Mechanism of Balance

The maintenance of residue is done yesteryear the cerebellum through the semi circular canals. They are filled amongst endolymph too granules of CaCo₃ called Otoliths.

I when the creature moves, the endolymph circulate causing the pilus cells inward the ampulla to deed amongst the Otoliths. The pilus cells sets upwardly a nervus impulse to the cerebellum through the vestibular part of the auditory nerve. The encephalon interprets the seat of the animal. Appropriate reflexes are sent yesteryear the encephalon to restore the normal trunk position.

Spinning circular inward i direction for a long fourth dimension causes the endolymph inward the semi circular canal to selection upwardly speed. On stepping all of a abrupt the fluid continuous to deed causing i to experience the terra firma spinning round. This causes dizziness equally the pilus cells give a nervus impulse of spinning.

Step 3:

Care of the ear

The ear is a vital organ that needs to survive taken attention of

1.     Protect the ear from loud dissonance yesteryear wearing muff to trim the degree of audio reaching the ear.

2.     De-wax the ear from fourth dimension to fourth dimension to avoid blockages of the ear canal but non much to avoid desiccation

3.     Wash or gagle the ear  with mild disinfectant to trim spread of microbes via Eustachian tube

4.     Visit oticians regularly to banking company fit for the wellness of the ear

5.     Treat whatever illness similar otitis media, ear ache, ear discharge

Evaluation

1.     Make  a good labelled diagram of the mammalian ear

2.     List the components of the

a.     Outer ear

b.     Middle ear

c.      Inner ear

3.     The sensitive pilus cells of the cochlea are called __________

4.     State the functions of the Eustachian tube

5.     Describe how the ear hears

Summary:

The cochlea too the semicircular canals are the ear components which functions inward hearing too balance. The 3 chambers of the ear piece of employment together to foster the workability of the ear.

Oticians are doctors who attention for the ear

Home work:

Describe what happens when somebody spins too all of a abrupt stops; why does he experience dizzy