Question

Several hours following death the muscles of the body stiffen, a condition commonly referred to as rigor mortis. What is the cause for the stiffened muscles?Myosin heads are not attached to actin filamentsMyosin heads are attached to actin filamentsActin degenerationMyosin degenerationBuild up of ATP due to lack of circulation

Answer 1

Myosin heads are attached to actin filaments

Step-by-step explanation:

During the process of muscle contraction, myosin heads are attached to actin filaments. ATP is necessary for their release and for the muscle relaxation.

In rigor mortis, myosin heads continue binding with the active sites of actin proteins. This occurs because after death, there is no production of ATP and consequently, the muscle is unable to relax until further enzyme activity degrades the complex.