The muscles of a recently deceased human can remain in a contracted state, termed rigor mortis, for several hours, due to the lack of
A) phosphorylated myosin.
B) ATP needed to break actin-myosin bonds.
C) calcium ions needed to bind to troponin.
D) oxygen supplies needed for myoglobin.
E) sodium ions needed to fire action potentials.

Question

Quizplus · Accepted Answer

Rigor mortis occurs due to the lack of ATP needed to break actin-myosin bonds. Without ATP, the cross-bridges between actin and myosin cannot be released, leading to muscle stiffness. None of the other options are directly involved in rigor mortis.

The Muscles of a Recently Deceased Human Can Remain in a Contracted