Across
- 2. synapse between a motor neuron and a skeletal muscle fiber
- 4. phenomenon in which a muscle fiber contracts when it is exposed to a stimulus of threshold strength
- 6. oxygen carrying pigment in Red Blood Cells
- 8. another protein that is part of the actin filament
- 11. continuous forceful muscular contraction without relaxation
- 12. the amount of oxygen required after physical excersize to convert accumulated lactic acid to glucose
- 13. a protein that forms filaments that slide between filaments of the protein myosin, contracting muscle fibers
- 15. a pigmented protein in muscle that carries oxygen
- 16. chemical that an axon end secretes on an effector or another neuron
- 19. a protein that, with actin, contracts muscle fibers
- 21. layers of fibrous tissue, separate individual skeletal muscles from adjacent muscles and hold it in place
- 26. specialized portion of muscle fiber membrane at an effector
- 27. protein that is part of the actin filament
- 28. stimulus stimulation level that must be exceeded to elicit a nerve impulse or a muscle contraction
- 29. membranous channel that extends inward from a muscle fiber membrane
- 30. time between application of a stimulus and the beginning of a response in a muscle fiber
- 31. a muscle biochemical that stores energy
Down
- 1. membranous network of channels and tubules of a muscle fiber, corresponding to the endoplasmic reticulum of other cells
- 3. a sheet of connective tissue that attaches muscles
- 5. structural and functional unit of a myofibril segment that extends from one zline to the next
- 7. a response to nerve impulses that originate repeatedly from the spinal cord and stimulate muscle fibers.
- 9. a group of enzymes that catalyze the hydrolysis of a phosphate bond in adenosine triphosphate (ATP) to form adenosine diphosphate (ADP)
- 10. a neuron that transmits impulses from the central nervous system to an effector
- 14. increase in number of motor units activated as stimulation intensity increases
- 17. a brief contraction of a muscle fiber followed by a relaxation
- 18. increased force of contraction by a skeltal muscle fiber when a twitch occurs before the previous twitch relaxes
- 20. A neuron that transmits impulses from the central nervous system to an affector
- 22. an enzyme that catalyzes the breakdown of acetylcholine
- 23. describes the process used by muscles to contract. It is a cycle of repetitive events that causes actin and myosin myofilaments to slide over each other, contracting the sarcomere and generating tension in the muscle.
- 24. Contractile fibers in muscle cells
- 25. a recording of a muscle contraction