Sliding Filament Theory Quiz

What gives skeletal muscle fibers their striated appearance?

• The presence of mitochondria

• The arrangement of actin and myosin filaments

• The presence of troponin

• The influx of calcium ions

Which ion is crucial for initiating muscle contraction by binding to troponin?

• Potassium

• Sodium

• Calcium

• Magnesium

What is the role of ATP in the muscle contraction cycle?

• It binds to myosin to cause detachment

• It causes the conformational change in actin

• It binds to actin to initiate contraction

• It provides energy for the power stroke

During which step does the myosin head change to a ready position?

• Power stroke

• Crossbridge formation

• Hydrolysis

• Detachment

What happens during the power stroke in the muscle contraction cycle?

• ADP and phosphate are released

• ATP binds to myosin

• Myosin detaches from actin

• Calcium ions bind to troponin