What does the sliding filament theory primarily explain?

• The process of bone growth

• The structure of the heart

• The mechanism of muscle contraction

• The function of the nervous system

What is the role of acetylcholine in muscle contraction?

• It provides energy for contraction

• It blocks the actin-myosin interaction

• It releases calcium ions

• It carries the signal to muscle fibers

How does calcium influence the interaction between actin and myosin?

• It provides energy for the interaction

• It exposes the binding sites on actin

• It blocks the binding sites on actin

• It breaks down ATP

What is the role of ATP in muscle contraction?

• It releases calcium ions

• It provides energy for the powerstroke

• It blocks the actin-myosin interaction

• It carries signals to the muscle fibers

What happens to the muscle when the activation signal stops?

• Calcium remains in the sarcoplasmic reticulum

• Muscles stay contracted

• Muscles return to a resting state

• Tropomyosin exposes the binding sites