BIOLOGY:CONCEPTS+APPL.(LOOSELEAF)
10th Edition
ISBN: 9781305967359
Author: STARR
Publisher: CENGAGE L
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Chapter 32, Problem 2CT
After death, a person no longer makes ATP, so calcium stored in the sarcoplasmic reticulum diffuses down its concentration gradient into the muscle cytoplasm. This result is rigor mortis----an unbreakable state of muscle contraction that stiffens the body for a few days until muscles begin to decay. Explain why this contraction occurs.
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You are a brilliant (but evil) biochemist who is developing a toxin that can be used to paralyze skeletal muscle. Using your knowledge of how muscle contraction happens at the cellular and molecular levels, identify two steps in the sequence of events necessary for the contraction that could be disrupted to cause paralysis, and explain why each disruption would prevent muscle contraction.
After death, a person no longer makes ATP, and calcium stored in the specialized endoplasmic reticulum of muscle fibers diffuses down its concentration gradient into the muscle cytoplasm. The result is rigor mortis—an unbreakable state of muscle contraction. Explain why the contraction occurs and why it is irreversible.
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