Muscular System

3. The site that undergoes most of the movement when a muscle contracts
6. The main inspiratory muscles
10. Muscles that decrease the thoracic cavity size
11. Muscle cell membrane
14. A key motor protein, particularly important for muscle contraction
15. A delicate connective tissue layer
17. Bundles of interconnected protein filaments of striated muscles
19. A muscle that helps another muscle perform a particular function effectively
20. Made up of thin actin filaments

1. Skeletal muscle cells
2. A muscle that stabilizes or fixes a part of the body to which a muscle in the process of moving another part is attached
4. Muscles that increase the size of the thoracic cavity when they contract
5. A sheath of fibrous elastic tissue surrounding a muscle
7. Sites where the ends of motor nerve fibers connect to muscle fibers
8. A sheet-like, fibrous connective tissue that serves as an attachment point for muscles
9. A fibrous connective tissue that attaches muscle to bone
12. A muscle or muscle group that directly produces a desired movement
13. Part of skeletal muscle
16. Basic contracting unit of skeletal muscle
18. The attachment site that doesn't move during contraction