<prompt> Answer this question truthfullyWhat happens after the ryanodine receptor is opened, with respect to the binding of Ca2 and troponin C, and how does this affect the binding of actin and myosin filaments?  <response>: <reason> After the ryanodine receptor is opened, the Ca2 that is released binds to troponin C. This induces a conformational change that moves tropomyosin out of the myosin-binding groove on actin filaments, allowing actin-myosin binding. 