Which regulatory protein does calcium bind to in order to initiate smooth muscle contraction?
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Correct answer: Calmodulin
Smooth muscle does not have troponin. Instead, four calcium ions bind to calmodulin, forming a complex that activates the enzyme Myosin Light Chain Kinase (MLCK).
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More Smooth Muscle Histology questions
- Which enzyme is responsible for phosphorylating the myosin head to allow it to bind to actin in smooth muscle?
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- Which of the following is true regarding the sarcoplasmic reticulum (SR) in smooth muscle compared to skeletal muscle?
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