Ch 16 Equilibrium Flashcards
Different types of equilibrium
static and dynamic
Static equilibrium definition
perception of the orientation of the head
Dynamic equilibrium definition
perception of motion or acceleration
Ampulla definition
dilated sac at one end of each semicircular duct
Ampullary cupula definition
gelatinous cap the extends form the crista to the roof of the ampulla
Ampullary crest definition
mound of hair and supporting cells within the ampulla
Process of equilibrium for head rotation in the semicircular canals
- head moves so endolymph in ampulla moves, then ampullary cupula moves
- hair cells in ampullary crest move
- hair cells alter rate of neurotransmitter release to surrounding sensory cells
- sensory cells propagate action potentials through sensory nerve
Utricle definition
posterior chamber in the inner ear that detects linear acceleration
Saccule definition
anterior chamber in the inner ear that detects static equilibrium
What are maculas?
patch of hair and supporting cells in the saccula and utricle
Two types of maculas
macula sacculi and macula utriculi
Macula sacculi movement
verticle
Macula utriculi movement
horizontal
Otoliths definition
protein calcium carbonate granules which add to the inertia of the membrane and enhance the sense of gravity and motion
Otolithic membrane definition
Process of equilibrium for acceleration and gravity
- acceleration causes head to tilt
- head tilt makes otoliths move
- hair cells are moved
- info about hair movement to sensory cells
Neural pathway for equilibrium
- sensory neurons to vestibular ganglia
- vestibular nerve
- combine with cochlear nerve to vestibulocochlear nerve
- synapse at vestibular nuclei between pons and medulla oblongata
What are the sensory receptors for hearing and equilibrium?
- three semicurcular ducts that detect angular acceleration, saccule, utricle
What is the vestibular apparatus?
receptors for equilibrium
