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Chapter 6 - The Muscular System
Across
1. Connective tissue enveloping bundles of muscle fibers.
4. Chemical released by neurons that may, upon binding to receptors of effector cells, stimulate or inhibit them.
6. Spindle shaped cells with one centrally located nucleus and no externally visible striations (bands). Found mainly in the walls of hollow organs.
9. Muscle composed of cylindrical multinucleate cells with obvious striations; the muscle(s) attached to the body's skeleton; voluntary muscle.
11. Chemical transmitter substance released by some nerve endings at neuromuscular junction.
13. Rodlike bundle of contractile filaments (myofilaments) found in muscle cells.
14. One of the principal contractile proteins found in muscle. Thick filament.
16. Region where a motor neuron comes into close contact with a skeletal muscle cell.
17. Sheath of fibrous connective tissue surrounding a muscle.
18. Functional junction or point of close contact between two neurons or between a neuron and an effector cell like a muscle.
Down
2. A motor neuron and all the muscle cells it stimulates.
3. Product of anaerobic metabolism, especially in muscle.
5. A muscle cell.
7. Bundle of muscle fibers bound together by connective tissues.
8. The smallest contractile unit of muscle; extends from one Z disc to the next.
10. Thin connective tissue surrounding each muscle cell.
12. The response of a muscle to a single brief threshold stimulus.
15. A contractile protein of muscle. The thin filament.