Muscle Physiology Quiz

What type of muscle is under voluntary control?

• Smooth muscle

• Visceral muscle

• Cardiac muscle

• Skeletal muscle

Which muscle type is found only in the heart?

• Striated muscle

• Cardiac muscle

• Smooth muscle

• Skeletal muscle

What is the cytoplasm of muscle cells called?

• Plasma

• Cytosol

• Myoplasm

• Sarcoplasm

What are the two types of contractile protein filaments in muscle fibers?

• Actin and troponin

• Myosin and tropomyosin

• Actin and myosin

• Myosin and calmodulin

What structure connects actin filaments to Z discs?

• A bands

• I bands

• Cross-bridges

• Sarcomeres

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

• Acetylcholine

• Myosin heads

• Sodium ions

• Action potential

What is the primary source of ATP during intense exercise?

• Anaerobic glycolysis

• Aerobic glycolysis

• Creatine phosphate

• Fatty acids

What condition results from the rapid decay of contractile proteins due to disuse?

• Muscle hypertrophy

• Muscle atrophy

• Myasthenia gravis

• Muscle strain

What is the role of calcium ions in muscle contraction?

• Stimulate ATP production

• Inhibit actin

• Activate myosin

• Uncover active sites on actin

What is the function of the myosin head during contraction?

• Bind to actin

• Store calcium

• Act as an ATPase

• Release acetylcholine