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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Which of the following is NOT true for a smooth muscle?
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The correct answer is  There are no Z-lines in smooth muscle. Z-lines are replaced with dense bodies. Thin : thick filament ratio is 15 : 1. When Ca2+ combines with calmodulin, there is activation of the enzyme myosin light chain kinase (MLCK), and the actin-myosin interaction can begin. Myosin light chains in the thick filament thus regulates the contraction. "Latch-bridge" phenomenon causes smooth muscle to develop sustained tension for a lesser energy consumption.