What is the primary difference in the contraction mechanism of smooth muscle compared to skeletal muscle?
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Correct answer: Smooth muscle uses calmodulin instead of troponin to bind calcium
Smooth muscle does not have the troponin-tropomyosin complex. Instead, calcium binds to calmodulin, which then activates Myosin Light Chain Kinase (MLCK) to phosphorylate the myosin heads and initiate contraction.
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