A steer's muscle is approximately 75 percent water, 20 percent protein, and collectively 5 percent fat, carbohydrates, and minerals. To simplify a complicated biological structure, we can describe such a muscle as consisting mainly of bundles of microscopic muscle fibers bound together - much like a coaxial cable - inside tiny, semitransparent tubes of connective tissue. Without this tissue, the meat would be flaccid mass.
The quantity and firmness of connective tissue in a raw piece of meat are determined by three factors: the anatomical location of the cut of meat, the animal's activity, and the animal's age.
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