Across
- 2. surrounds each individual muscle fiber
- 4. inner material surround fibers
- 7. thin, light filaments
- 9. individual parallel muscle fibers within sarcoplasm
- 10. muscles become small and weak
- 11. where a nerve and muscle fiber come together
- 13. theory of how muscle contracts
- 14. fibers that are arranged in bundles
- 17. outermost layer of muscle
- 18. where neurotransmitters are stored
- 19. causes a person's muscles to contract and not relax
- 20. separates and surrounds fascicles
- 21. muscles enlarge
Down
- 1. a type of neurotransmitter involved in muscle contraction
- 3. joints become stiffen after death
- 5. first step in a muscle contraction
- 6. a sustained involuntary contraction
- 8. muscle fiber membrane
- 12. thick, dark filaments
- 15. gap between the neuron and motor end plate (synaptic cleft)
- 16. muscle loses ability to contract after prolonged use