Across
- 2. the concept that a sarcomere shortens as the thick and thin filaments slide past one another
- 4. another name for cardiac muscle cells
- 9. muscles that appear to have parallel lines or stripes due to the sarcomeres; skeletal and cardiac
- 12. involuntary muscle found in many organ systems that control organs
- 14. filaments of connective tissue that surround cardiac muscle cells to insulate and help them keep their shape
- 16. muscle muscle that is under conscious control; skeletal muscle
- 17. involuntary muscle tissue found only in the heart.
- 18. a muscle that serves to bend a limb
- 19. muscle that is attached to the bones of the skeleton and provides the force that moves the bones.
- 21. specialized nerve cells that send signals from the brain and spinal cord to the muscles and cause them to contract or relax
- 22. another name for a muscle cell
- 23. muscle muscle that is not under conscious control, but controlled automatically by the brain; smooth and cardiac
Down
- 1. tightly packed filament found within skeletal muscle fibers
- 3. the thin filaments of protein in a muscle fiber
- 4. the thick filament of protein in a muscle fiber
- 5. muscle pairs arranged to work against each other to move a joint
- 6. specialized cells located in the heart that sends out signals to keep the heart beating regularly
- 7. powerhouse of the cell; 10x more abundant in cardiac muscle cells to keep the heart from getting tired
- 8. specialized connections between cardiac muscle cells
- 10. the ends of the sarcomere that are "zig-zaggy" and separate each sarcomere
- 11. muscles that do not have sarcomeres, therefore do not appear to have parallel lines or sarcomeres
- 13. inability of muscle to maintain force of contraction after prolonged activity
- 15. a unit of a striated muscle fiber that causes the muscle to contract
- 20. a muscle that straightens a joint
- 21. more than one nucleus per cell; skeletal muscle