Question

Choose one of the major sensory systems (smell, taste, vision, hearing, balance, or touch) and explain in detail how a sensory stimulus is transduced into an action potential.

Answer 1

In hearing we need to convert the sound waves to electrical signals so as transport through the nerves. Thus conversion is known as signal transduction.

The sound waves are collected with the help of pinna and it moves through the ear canal. The sound waves reaching the tympanic membrane vibrates it. The tympanum is connected with the earbones malleus, incus and stapes. These carry the impulse and reach the cochlea. There is a specialised part called organ of corti inside the cochlea responsible for hearing. There are vestibular fluids in the organ of corti. The vibration reachin the chochlea is transmitted throught the vestibular fluids in scala vestubuli which thereby vibrates the fluid in the scala tympani. The organ of corti situated between these two compartments recieves the vibration. The organ of corti present in the basilar membrane if the inner cochlear duct has specialised hair cells. When the vubratuo reach the Cochlear duct the hair cells slides against the tectorial membrane situated above it. The sliding of the hair cells will be in the opposite direction of vibration. The hair cells sliding in the tectorial membrane produces an electric signal. This signal is transported through the auditory nerve. Thus the impulse reach the brain auditory centre and we can sense the sound.