After death, rigor mortis develops as levels of calcium in the sarcoplasm increase and levels of __________ decrease.
A) ATP
B) ADP
C) sodium
D) potassium
E) myoglobin

Question

Quizplus · Accepted Answer

Rigor mortis occurs because the muscles are unable to relax due to the lack of ATP, which is necessary for muscle relaxation. As ATP levels decrease, calcium ions cause the muscles to contract, but without ATP, the muscles cannot relax, leading to the stiffening known as rigor mortis.

After Death, Rigor Mortis Develops as Levels of Calcium in the Sarcoplasm