Geotaxis in protozoa I. A propulsion-gravity model for Tetrahymena (Ciliata).
D000818:Animals; D002465:Cell Movement; D002923:Cilia / Q000502:physiology; D006112:Gravitation; D008954:Models, Biological; D009949:Orientation; D011312:Pressure; D013769:Tetrahymena pyriformis / Q000502:physiology*; D014783:Viscosity