Skeletal Muscles

1. Bundles of muscle cells
3. Vesicles inside the axon terminal containing acetylcholine
6. Protein in thin filaments
7. Middle of each Aband
11. Part of the motor neuron connecting to the muscle fiber
15. Polarized state of a muscle fiber when not being stimulated
17. Connective tissue between bones and muscles
18. Connective tissue around the entire muscle
20. Connective tissue around fascicles
21. Connect neighboring filaments
22. tubes of the sarcolemma extending deep into the cell
25. Second name for muscle cells
26. Plasma membrane of a muscle cell
27. Contains myofilaments; contractile unit of a muscle cell
28. Elongated cells with multiple nuclei with visible striations
29. Space between the axon terminal and the motor end plate of the sarcolemma
30. Areas of thick filaments; dark in color
31. Spindle shaped cells with a single, central nucleus and no visible striations

2. Electric impulse that depolarizes a muscle fiber and causes it to contract
4. Endoplasmic reticulum of a muscle cell; surrounds myofibrils
5. Intracellular fluid
8. Thick and thin filaments in myofibrils
9. Folded part of the sarcolemma that interacts with the motor neuron
10. In thin filaments; connects myofibrils
12. In between two Z lines
13. Sacs of calcium ions
14. Connective tissue around muscle cells; electrically insulates cells from one another
16. T tubule between two adjacent terminal cisternae
19. Areas of thin filaments; light in color
23. Branching cells with a single peripheral nucleus and visible striations
24. Neuron that stimulates contraction of muscle fibers
27. Protein in thick filaments