True regarding movements of the cilia in the inner ear are all except: March 2009
High-Yield Explanation
Ans. C: It moves when perilymph moves Into the cupula are projected hundreds of cilia from hair cells located on the ampullary crest. When the head suddenly begins to rotate in any direction (angular acceleration); the endolymph in the semicircular canals, because of its ineia, tend to remain stationary while the semicircular canals turn. This cause relative fluid flow in the ducts in the direction opposite to the head rotation. Similarly When the rotation stops suddenly: the endolymph continues to rotate. And this time cupula bends in opposite direction, causing hair cells to stop discharging entirely.