What causes the rigor mortis that occurs in skeletal muscles after death?
A) Increase in available ATP, and decreased membrane permeability to calcium ions
B) Decrease in available ATP, and increased membrane permeability to calcium ions
C) Persistent stimulation by motor neuron
D) Decrease in the number of muscle fibers
E) Increase in membrane leakiness to sodium, resulting in continuing action potentials

Question

Quizplus · Accepted Answer

Rigor mortis occurs due to a decrease in available ATP, which is necessary for muscle relaxation, and an increase in membrane permeability to calcium ions, which triggers muscle contraction. After death, ATP synthesis stops, preventing muscle relaxation, while calcium ions leak into muscle cells, initiating contraction without the ability to relax, leading to the stiffening known as rigor mortis.

What Causes the Rigor Mortis That Occurs in Skeletal Muscles