Unit 1 - Mechanoreception and Chemoreception Flashcards
Outer Ear
1) Auricles (Pinna)
2) Auditory Canal
Middle Ear
Air Filled
1) Tympathic Membrane (Eardrum)
2) Eustachian Tube
3) Ossicles
Inner Ear
Fluid filled.
1) Semi-Circular Canals
2) Cochlea
Organ of Corti
Where mechanoreceptors are located.
–> Hair cells contain thin projections called STEREOCILIA detect soundwaves. As soundwaves travel through cochlea, stereocilia bends, converting nerve impulse to the brain.
Pathway of Sound Through the Ear
Auricles –> Auditory Canal –> Tympathic Membrane –> Ossicles –> Oval Window –> Cochlea –> Organ of Corti –> Hair cells
Sound Perception
Auditory Nerve takes nerve impulses out of cochlea.
–> Nerve impulse travels first to thalamus then to temporal lobe.
Other Mechanoreceptors
PROPRIOCEPTORS: in muscles and joints, sends signal to cerebellum for coordination.
Taste / Smell
Taste: Chemoreceptors on the tongue, signal goes to thalamus then to gustatory centre (parietal lobe).
Smell: Chemoreceptors inside the nasal cavity (OLFACTORY CELLS), signal goes to olfactory centre in frontal lobe.
Auricles (Pinna)
Skin & cartilage, collect & funnel soundwaves into the ear.
Auditory Canal
Sound waves funnel into it.
–> Contain hair & earwax to protect the ear, prevent entry of foreign material.
Tympathic Membrane (Eardrum)
Covers end of auditory canal, converts soundwaves to mechanical vibrations.
–> Tympathic membrane passes vibration to three ossicles (bones).
Eustachian Tube
Allow pressure to equalize between middle and outside of body.
–> Connects middle ear to back of throat. NOT INVOVLED IN HEARING!!
Three Ossicles
1) Melleus (hammer)
2) Invus (anvil)
4) Stapes (stirrups).
Semi-Circular Canals
Contains receptors for balance.
Cochlea
Organ of hearing, soundwaves converted to nerve impulses to the brain.
