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Coordination in animals

Mechanism of hearing increase the force of vibration and as a result
it amplifies the sound waves.
Task 2.10
Search from the library and internet The vibrations of the stapes against the
sources for animations about the oval window set up waves in fluids in the
FOR ONLINE READING ONLY
mechanism of hearing. Watch the videos cochlea. The vibrations of the fluid cause
and with relevant diagrams write short the basilar membrane to vibrate. This
notes about your observation. stimulates the sensory hair cells (organ

of corti) on basilar membrane to send
The pinna collects sound waves from the the nerve impulses to the brain through
surroundings and direct them to the middle auditory nerves. When the waves reach the
ear through external auditory meatus which auditory area of the cerebral cortex, they
end up to the tympanic membrane. Sound are interpreted as sound. The magnitude
waves cause the membrane to vibrate. When of the impulses transmitted to the brain
the tympanic membrane vibrates back and determines the pitch or loudness of the
forth, it forces the ossicles that is malleus, sound. The louder the sound, the greater
incus and stapes to vibrate in the same the number of sensory hair cells that will
way. This causes the stapes to move rapidly be stimulated at any point of the basilar
forwards and backwards like a piston in membrane. See Figure 2.18.
the oval window. The connected ossicles

Sensory hair cells
Pinna Incus
Malleus Stapes Basilar membrane
Oval window

Sound waves Ear drum Eustachian tube Cochlea
Figure 2.18: Mechanism of hearing

Mechanisms of body balance The semicircular canals and vestibular
Task 2.11 apparatus (utriculus and succulus) shown
in Figure 2.19 are concerned with balance
Search from the library and internet of the body. They contain sensory receptors
sources for animations about the human which detect movements of the head. The
body balance. Watch the videos and with three semicircular canals contain fluid
aid of relevant diagrams, write short called endolymph which communicates
notes about your observation. with the middle chamber of the cochlea
via the utriculus and sacculus. When the

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