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muscle
muscle Muscle is a specialized contractile tissue that produces animal movement by shortening when stimulated and drawing its points of attachment closer together.
Muscle is a specialized contractile tissue that produces animal movement by shortening when stimulated and drawing its points of attachment closer together. In humans and other higher vertebrates, it includes smooth muscle of the internal organs and blood vessels, heart muscle, and voluntary skeletal muscle that makes up most of the body's fleshy parts.