The vestibular system consists of which two subsystems?

The vestibular system, which is crucial for maintaining balance and spatial orientation, is composed of two primary subsystems: the semicircular canals and the otolith organs. The semicircular canals are three looped structures positioned at right angles to each other, responsible for detecting rotational movements of the head. They contain fluid that moves in response to head rotation, stimulating sensory receptors and providing information about angular acceleration.

The otolith organs, consisting of the utricle and saccule, respond to linear accelerations and the effects of gravity. They contain small crystals called otoliths that shift in response to movement, helping the brain understand the position of the head relative to the ground and movement in a straight line.

Together, these two subsystems work synergistically to provide the brain with comprehensive information about motion and position, allowing for effective balance and coordination. Other options presented do not correctly represent components of the vestibular system; they include structures that are not involved in balance or are part of different sensory systems.