| A | B |
|---|
| smooth muscle | type of involuntary muscle found in the walls of internal organs and blood vessels |
| cardiac muscle | type of involuntary muscle found only in the heart |
| skeletal muscle | a type of voluntary muscle that is attached to and moves the bones of the skeletion |
| myofibrils | unit of the muscle fibers composed of thick myosin protein filamentsand thin actin protein filaments |
| sarcomeres | each section of a myofibril in muscle |
| sliding filament theory (SFT) | theory that actin filaments slide toward each other during muscle contraction while the myosin filaments are still |
| myosin | structural protien that makes up the thick filaments of myofibrils |
| actin | structural protien that makes up the thin filaments of the myofibrils |
