Hearing Flashcards
What is the organ of hearing?
The ear
What are the functions of the ear?
2
Hearing
Balance
Name the three sections of the ear.
The outer ear
The middle ear
The inner ear
What is the inner ear filled with?
A liquid called lymph
What is the outer and middle ear filled with?
Air
What part of the ear is filled with lymph?
The inner ear
What parts of the ear are filled with air?
The outer and middle ear
What causes sound?
Vibrations in the air
What is the pinna?
2
Part of the outer ear made mostly of cartilage
It helps to collect and channel vibrations into the auditory canal
What section of the ear is the pinna a part of?
The outer ear
What is the pinna mostly made of?
Cartilage
What is the function of the pinna?
It helps to collect and channel vibrations into the auditory canal
The pinna helps collect and channel vibrations into what part of the ear?
The auditory canal
What part of the ear helps to collect and channel vibrations into the auditory canal?
The pinna
What is the auditory canal?
2
The tube which carries vibrations to the eardrum
Secrets wax outside of the eardrum to trap dust particles and protect the ear
What does the auditory canal carry to the eardrum?
Vibrations
The auditory canal carries vibrations to what part of the ear?
The eardrum
What does the auditory canal secrete?
Wax
Where does the auditory canal secrete wax?
Outside the eardrum
What is the function of wax?
To trap dust and protect the ear
What is the eardrum?
A small, tightly stretched membrane which separates the outer ear form the middle ear and vibrates as a result of the vibrations that reach it.
Describe the eardrum.
A small, tightly stretched membrane
What is the function of the auditory canal?
2
Carries vibrations to the eardrum
Secretes wax
What is the function of the eardrum?
2
Separates the outer and middle ear
Vibrates when the vibrations reach it
What happens when vibrations reach the eardrum?
The eardrum vibrates
What are the ossicles?
3
Three tiny bones in the middle ear
(hammer, anvil and stirrup)
They transmit vibrations from the outer to the inner ear and amplify vibrations
Name the three ossicles.
Hammer
Anvil
Stirrup
Which ossicle is the smallest?
The strirrup
What is the function of the ossicles?
2
They transmit vibrations from the outer to the inner ear
They amplify vibrations
Write a note on the Eustachian tube.
3
Not technically part of the ear
It is a tube which runs form the middle ear to the the pharynx
Equalises pressure on either side of the eardrum thus preventing damage to the eardrum caused by differences in pressure between the outer and inner ear.
What is the Eustachian tube?
It is a tube which runs form the middle ear to the the pharynx
Where does the Eustachian tube run to and from?
From the middle ear to the pharynx
What are the functions of the Eustachian tube
2
Equalises pressure on either side of the eardrum
This prevents damage to the eardrum caused by differences in pressure between the outer and inner ear.
What type of damage does the Eustachian tube prevent from happennening to the eardrum?
It prevents damage to the eardrum caused by differences in pressure between the outer and inner ear.
Write a note on the cochlea.
3
A spiral tube which is 3.5cm long
It is responsible for hearing
This is because it converts pressure waves into electrical impulses which travel to the brain
What shape is the cochlea?
It is a spiral tube
How long is the cochlea?
3.5cm long
What are the functions of the cochlea?
2
Responsible for hearing
Converts pressure waves into electrical impulses
Why is the cochlea considered to be responsible for hearing?
This is because it converts pressure waves into electrical impulses which travel to the brain
Write a note on how the cochlea works.
5 steps
Vibrations arrive at the cochlea from the stirrup which attaches to a membrane in the cochlea called the oval window
Vibrations pass through oval window and form pressure waves in lymph in the cochlea
Pressure waves stimulate receptors in the cochlea (hairs attached to 24,000 sensory cells located along the cochlea)
Receptors cause electrical impulses to be sent to the brain which travel along the cochlear nerve
Pressure waves are allowed to dissipate out of the cochlea into the air of the middle ear by the round window
How do vibrations arrive at the cochlea?
Vibrations arrive at the cochlea from the stirrup which attaches to a membrane in the cochlea called the oval window
What is the stirrup attached to?
The oval window
What is the oval window?
A membrane in the cochlea which attaches to the stirrup
What is the function of the oval window?
2
Vibrations pass from the stirrup to the attached oval window
These vibrations then pass through the oval window and form pressure waves in lymph in the cochlea
Where are pressure waves formed?
In lymph
What happens after pressure waves have been formed in lymph?
These pressure waves stimulate receptors in the cochlea
What are the receptors in the cochlea?
2
These are hairs that are attached to 24, 000 sensory cells located along the length of the cochlea
These cells collectively form a structure called the Organ of Corti
What is the Organ of Corti?
The Organ of Corti is the name given to the collective 24,000 sensory cells located along the length of the cochlea
What are attached to the Organ of Corti?
Hairs
What are the functions of receptors (hairs attached to the Organ of Corti)?
Receptors cause electrical impulses to be sent to the brain which travel along the cochlear nerve
What do the electrical impulses travel along?
The cochlear nerve
What happens after the electrical impulses have been sent to the brain?
Pressure waves are allowed to dissipate out of the cochlea into the air of the middle ear by the round window
What allows the pressure waves to dissipate out of the cochlea into the air of the middle ear?
The round window
Where is balance detected in the ear?
The vestibular apparatus in the inner ear
What does the vestibular apparatus mainly consist of?
Three semicircular canals
What is the vestibular apparatus filled with?
A liquid called lymph
What do the receptors of the vestibular apparatus detect?
2
Whether the head is vertical or not
Movement of the head
What is the function of the receptors in the vestibular apparatus?
They send impulses to the cerebellum of the brain through the vesitbular nerve
Through what does the vestibular apparatus send impulses to the cerebellum?
Through the vestibular nerves
Where does the vestibular apparatus send impulses to through the vestibular nerve?
The cerebellum of the brain
