Question

Rigor mortis is

• A. Contraction of muscles after death
• B. Contraction of muscles before death
• C. Shivering of muscles
• D. None of the above

Answer 1

The correct option is A Contraction of muscles after death

Rigor mortis is stiffening of the body caused by contraction of muscles after death. In humans it occurs four hours after death. Due to absence of oxygen after death, the ATP is not formed which is required for separation of actin and myosin. When oxygen is no longer present, the body may continue to produce ATP via anaerobic glycolysis. When the body's glycogen is depleted, the ATP concentration diminishes, and the body enters rigor mortis because it is unable to break those bridges. So, the correct answer is 'Contraction of muscles after death'.