Concept explainers
A few hours after the death of an animal, the corpse will stiffen as a result of continued contraction of muscle tissue (this state is called roof mortis). This phenomenon is the result of the loss of ATP production in muscle tissue.
a. Consult Figure 7.482 and describe, in terms six-step model of muscle contraction, how a lack of ATP in sarcomeres would result in rigor mortis.
b. The Ca2+ transporter in sarcomeres that keeps the [Ca2+] ~ 10-7 M requires ATP to drive transport of Ca2+ ions across the membrane of the sarcoplasmic reticulum. How would a loss of this Ca2+ transport function result in the initiation of rigor mortis?
c. Rigor mortis s maximal at ̀´ 12 hrs after death by 72 hrs is no longer observed. Propose an explanation for the disappearance of rigor mortis after 12 hrs.
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Biochemistry: Concepts and Connections (2nd Edition)
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