title: The involvement of pH, adenosine triphosphate, calcium, and magnesium in the contraction of the glycerinated stalks of Vorticella.
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism*; D000818:Animals; D002118:Calcium / Q000378:metabolism*; D016798:Ciliophora / Q000378:metabolism*; D005990:Glycerol; D006863:Hydrogen-Ion Concentration; D066298:In Vitro Techniques; D008274:Magnesium / Q000378:metabolism*; D009119:Muscle Contraction / Q000502:physiology*; D009124:Muscle Proteins / Q000378:metabolism*
chemical_list: D009124:Muscle Proteins; D000255:Adenosine Triphosphate; D008274:Magnesium; D005990:Glycerol; D002118:Calcium