Rigor mortis occurs after a person dies because muscle cells are no longer supplied with ATP. This causes the muscles to become rigid and stuck in position. Based on your knowledge of muscle contraction, why would muscles become rigid, rather than limp, after death?

Biology by Geoffrey
  1. Rigor mortis occurs after a person dies because muscle cells are no longer supplied with ATP. This causes the muscles to become rigid and stuck in position. Based on your knowledge of muscle contraction, why would muscles become rigid, rather than limp, after death?
  2. The term fibrillation refers to an irregular, ineffective heartbeat. Do you think ventricular fibrillation is more or less serious than atrial fibrillation in a human? Explain your reasoning.