Across
- 1. Attached to Z-Lines
- 4. Individual Contractile units
- 6. Sits between two actin filaments and connect at the M-Line
- 7. when Ca+ enters the myofibril, it binds to this
- 9. A fluid-filled net of membranes that surrounds each myofibril
- 10. An increase in this, initiates muscle contractions
- 11. Calcium is pumped back into the SR by this
- 13. Nerve signals trigger the release of this
- 15. The change in charge inside the sarcolemma
- 16. Surrounds each muscle fiber
- 17. Composed of thousands of fibers that contract together
- 18. Surrounds entire muscle
- 19. Contractile unit composed of Actin and Myosin
Down
- 2. Continuous with sarcolemma
- 3. SR becomes leaky/ Unbroken Cross bridges
- 5. Site where motor neurons attach to muscle fibers at the motor end plate
- 6. Muscle Cells
- 8. Model that describes how myosin walks along actin
- 12. surrounds fascicles and contains blood vessels and nerves
- 14. Increases permeability of the SR to Ca2+