Physiology All of the following are true about excitation-contraction coupling except A Acetylcholine is released at the nerve terminal B Calcium is pumped back into the sarcoplasmic reticulum during relaxation C Calcium is released from sarcoplasmic reticulum during contraction. D Calcium binds to tropomyosin to initiate muscle contraction. 💡 Explanation All of the following are true about excitation-contraction coupling except ✓ Correct Answer: D. Calcium binds to tropomyosin to initiate muscle contraction.