A&P - Chapter 24 (Part 3) Flashcards
How is sound created?
By vibrations
What does the ability to hear waves depend on? (3)
- Volume
- Pitch
- Other acoustic properties
What must sound waves be of in order to move the tympanic membrane and have a frequency capable of stimulating the hair cells in the organ of corti?
Sufficient amplitude
What does hearing result from?
Stimulation of the auditory area of the cerebral cortex
What is the only part of the inner ear that is involved with hearing?
The cochlea
What does the vestibule hold? (2)
- Utricle
2. Saccule
What is another term for utricle and saccule?
Otolith organs
What does both utricle and saccule contain?
Macula
Macula
Contain receptor hair cells covered by a gelatinous membrane that contains particles of calcium carbonate
- otoliths
Otoliths
Ear stones
What causes the otoliths to move?
Movement of the head
What does movement of the otolith stimulate?
The hair cells of the macula
- which then stimulates the vestibular nerve
Where is the crista ampullaris located?
In the semicircular canals
What is the crista ampullaris involved with?
Balance
What is each crista covered with?
Hair cells that are embedded in a cupula
Cupula
Gelatinous structure
What causes movements of the cupula?
Movements of the head
What happens when the cupula moves?
It bends the hair cells
What happens when the cupula hair cells bend?
It stimulates the vestibular nerve
What are 2 forms of equilibrium?
- Static equilibrium
2. Dynamic equilibrium
What is involved with static equilibrium?
Vestibule
- utricle
- saccule
What is involved with dynamic equilibrium?
Semicircular canals
- crista ampullaris
Static equilibrium
Related to maintaining stability and posture when the head and body are not moving
- special senses that interprets the position of the head
Dynamic equilibrium
Lets the brain know if we have our balance during movement or if our body is in motion
- the special sense which interprets balance when we are moving (or at least our head is moving)
