Muscle Function and Contraction Quiz

Which type of muscle tissue is under voluntary control?

• Cardiac muscle

• Smooth muscle

• Skeletal muscle

• Involuntary muscle

What is the role of the neuromuscular junction?

• It stores calcium ions.

• It is the site where muscle fibers are produced.

• It is where the signal exchange between a neuron and muscle fiber occurs.

• It is responsible for muscle relaxation.

What happens during the power stroke in muscle contraction?

• Actin filaments are produced.

• Myosin pulls the actin filament toward the m-line.

• Calcium ions are released from the sarcoplasmic reticulum.

• ATP is synthesized.

How do calcium ions influence muscle contraction?

• They block the binding sites on actin.

• They cause muscle fibers to elongate.

• They bind to tropinin, exposing binding sites on actin.

• They are responsible for ATP production.

What triggers the release of calcium ions from the sarcoplasmic reticulum?

• The relaxation of muscle fibers

• The presence of ATP

• The binding of neurotransmitters to muscle fiber receptors

• The sliding of actin and myosin filaments