Graded responses in ciliary activity of ctenophores compared with the "staircase" of cardiac muscle.
D000818:Animals; D002923:Cilia / Q000502:physiology*; D003063:Cnidaria / Q000166:cytology / Q000502:physiology*; D004558:Electric Stimulation; D006321:Heart / Q000502:physiology*; D008954:Models, Biological; D010781:Photography; D013997:Time Factors