How do Muscles Contract? Sliding Filament Theory | Corporis Vide

What is the function of sarcomeres in muscle fibers?

• To provide structure for actin filaments

• To generate passive force

• To stabilize myosin filaments

• To slide past each other during muscle contraction

What are the parallel, overlapping proteins called in a sarcomere?

• Actin and myosin

• Tropomyosin and troponin

• Titin and myosin

• Nebulin and actin

What is the role of ATP in muscle contraction?

• To provide energy for the contraction

• To move tropomyosin out of the way

• To stabilize myosin filaments

• To generate passive force

What happens when myosin attaches to actin during muscle contraction?

• A power stroke occurs

• The muscle relaxes

• The muscle becomes stiff

• The muscle stretches

What is the function of calcium ions in muscle contraction?

• To provide energy for the contraction

• To move tropomyosin out of the way

• To stabilize myosin filaments

• To generate passive force

What are the three distinct zones in a sarcomere?

• I zone, A band, H zone

• I band, A zone, H band

• I band, A band, M zone

• I zone, A zone, M band

What happens if there is no ATP available for muscle contraction?

• The muscle becomes stiff

• The muscle relaxes

• The muscle stretches

• The muscle contracts normally

Where do calcium ions come from in muscle contraction?

• Sarcoplasmic reticulum

• Mitochondria

• Nucleus

• Golgi apparatus

What is the function of the Z line in a sarcomere?

• To provide structure for actin filaments

• To generate passive force

• To stabilize myosin filaments

• To mark the border of each sarcomere

What is the purpose of the power stroke in muscle contraction?

• To provide energy for the contraction

• To move tropomyosin out of the way

• To stabilize myosin filaments

• To slide the filaments forward