Which of the following statements about the muscle cell contractions is not true: In a relaxed state the, the thick and thin filaments do not fully overlap (only at the sides of the A band) Cross bridge formation occurs when myosin heads bind to actin filaments Contraction is stimulated by the binding of sodium to troponin When troponin changes shape, tropomyosin no longer blocks binding sites on actin for myosin. The creation of a cross bridge requires the hydrolysis of an ATP molecule
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In a relaxed state, the thick and thin filaments do not fully overlap (only at the sides of the A band). This statement is true. In a relaxed state, the thick and thin filaments partially overlap, with the thin filaments extending into the A band only at the Show more…
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