Figure 2. Temperature dependence of isometric tension for models with only one or two temperature-sensitive steps.

Dotted line: only the first tensing step is allowed to be temperature-sensitive. Grey line: only the hydrolysis step is allowed to be temperature-sensitive. Full line: both the hydrolysis step and the attachment of M.ADP.P_i to actin are allowed to be temperature-sensitive. In each case the temperature-sensitive steps had an enthalpy change of 120 kJ mol⁻¹ and an activation enthalpy of 140 kJ mol⁻¹. Tensions are normalised to their value at 2°C.