Which of the following provides the energy for cross-bridge cycling during muscle contraction

Question

Quizplus · Accepted Answer

ATP (adenosine triphosphate) provides the energy for cross-bridge cycling during muscle contraction. When ATP is hydrolyzed, energy is released and this energy is used to power the movement of the myosin heads, causing them to rotate and pull on the actin filament. This repeated cycle of ATP hydrolysis and myosin-actin interaction is what causes the muscle to contract. Acetylcholine is a neurotransmitter that initiates muscle contraction by triggering the release of Ca²⁺ from the sarcoplasmic reticulum, but it does not provide energy for cross-bridge cycling. Ca²⁺ is involved in muscle contraction by binding to troponin and exposing the binding sites on actin, but it does not directly provide energy for cross-bridge cycling. Myosin is a protein that interacts with actin to cause muscle contraction, but it does not itself provide energy for cross-bridge cycling.

Which of the Following Provides the Energy for Cross-Bridge Cycling