[An easy introduction to organismal and cellular mechanisms for graviperception]

In this review paper, organismal and also cellular mechanisms for perception of gravity are explained. A statolith and a number of hair cells which surround the statolith is a basic structure of statocysts for detecting the direction of gravity or tilting of the body in various animals. The vestibular system of vertebrate was explained, especially on the process from the body-tilting to impulse frequencies which travel to brain. For the cellular responses to gravity, contribution of various organella (??) and cytoskeleton are introduced. Such cellular responses may change when the gravity values become less or null. Gravity perception mechanisms of plants are also explained.