which are also striated in the same pattern of alternating dark and light bands. Bundles of fibers are bound together by connective tissue; the bundles, in turn, are bound together to form muscle. Striated muscle, which is the most common type of muscle as well as the most common type of tissue in humans, is stimulated by the somatic nervous system. Each cell of a muscle is excited by only one nerve fiber: Contraction occurs when nerve impulses are present, and relaxation occurs when nerve impulses are absent. Striated muscles perform adjustments to the body in response to its external environment. The muscles effect change through contraction by bending the skeletal structure, to which the muscles are attached by tendons, at moveable joints in the structure.
