___are thin filaments.

• troponin

• tropomyosin

• actin

• myosin

___are thick filaments.

• actin

• myosin

• troponin

• tropomyosin

___are regulatory proteins that cover the myosin binding site on the actin.

• troponin-tropomyosin

• sarcomere

• sarcolemma

• sarcoplasmic reticulum

Calcium binds to ___of the troponin-tropomyosin complex.

• troponin

• tropomyosin

• actin

• myosin

Calcium is stored in the ___.

• sarcoplasm

• sarcolemma

• sarcoplasmic reticulum

• transverse tubules

A ___extends from one Z disc to another Z disc.

• Sarcolemma

• Neuromuscular junction

• Sarcomere

• Motor end plate

___gets shorter during contraction.

• actin

• myosin

• troponin-tropomyosin

• none of these

___forms a crossbridge with actin.

• actin

• myosin

• calcium

• ATP

___provides energy for muscle contraction and relaxation.

• cAMP

• ADP

• ATP

• M line

___slides inward during muscle contraction.

• actin

• myosin