| A | B |
|---|
| sarcomere | one unit of contractile proteins |
| myofibril | an organell made of filaments |
| fiber | a muscle cell |
| fascicle | a bundle of muscle cells |
| fascia | outer covering of entire muscle |
| tendon | a muscle to bone connection |
| filament | made of many proteins which move during contraction |
| myosin | thick protein filaments |
| actin | thin protein filaments |
| ATP | energy molecule used in contraction |
| glucose | carbohydrate used to make ATP |
| sarcoplasmic reticulum | largest, total transport system for calcium |
| sarcolemma | a muscle cell membrane |
| mitochondria | organelle which supplies muscle contraction energy |
