Chapter 1 (1.2 : Ears) Flashcards
(28 cards)
The human ear divided into 3 parts which _____, _____ and _____. Fill in the blanks.
-Outer ear
-Middle ear
-Inner ear
What does the outer ear consists of?
-Ear pinna
-Ear canal
What is the function of ear pinna?
Collects and directs sound wave (vibrating air) into the ear canal (auditory canal)
What is the function of ear canal?
Directs sound waves to the eardrum
What does the middle ear consists of?
-Eardrum
-Ossicles
-Oval window
-Eustachian tube
What is the function of ear drum?
Vibrates at the same frequency as the sound waves that hit it and transfer the vibrations from the eardrum to the ossicles
What is the function of ossicles?
Amplify the vibrations and transfer the vibrations from eardrum to the oval window
What is the function of oval window?
Transfer the vibrations from ossicles to inner ear
What dos the inner ear consists of?
-Cochlea
-Auditory nerve
-Semicircular canals
What is the function of eustachian tube?
Helps balance the air pressure on both sides of the eardrum
What does the inner ear consists of?
-Cochlea
-Auditory nerve
-Semicircular canal
What is the function of cochlea?
Detects vibrations and converts them into nerve impulses
What is the function of auditory nerve?
Sends nerve impulses from the cochlea to the brain which interprets the messages as sound
What is the function of semicircular canals?
Helps to maintain body balance
Which part of the ear does not involved in hearing?
Semicircular canals
State the order of hearing mechanism.
1.The pinna gathers sound waves and directs them to the auditory canal.
2.The sound waves travel along the ear canal and reach the eardrum.It vibrates at the same frequency as the sound waves.
3.The vibration are transferred to the ossicles. The ossicles amplify the vibrations 20 times in magnitude before passing them to the oval window.
4.Vibrations of the oval window causes the fluid in the cochlea to vibrate.
5.The movement of the fluid stimulates the receptors in the cochlea. Nerve impulses are generated.
6.The auditory nerve sends the nerve impulses to the brain.
The brain interprets the messages as sounds.
How much Hz (hertz) can be detected by the human ear?
Frequency range of 20 Hz to 20 000 Hz
Why do people’s hearing deteriorates when they age?
Their eardrums become less elastic, hence their range of sound frequencies that they can detect decreases
What are frequencies exceeding 20 000 Hz called?
Ultrasonic frequencies
What examples of devices are used to overcome the limitations of hearing?
-Stethoscope
-Loudspeaker or megaphone
-Earphones
-Sonar
What is the common hearing defect?
Deafness
What does deafness refer to?
Deafness refers to partial or total hearing loss
Which part of the ear is involve in temporary hearing loss?
-Outer ear
-Middle eat
What is temporary hearing loss caused by?
-Build-up of earwax in auditory canal block sound waves
-Punctured eardrum
-Infections of ossicles
