Muscle tissue is comprised of groups of muscle cells, laid out in differing organizations depending on the muscle tissue type. For skeletal muscle tissue, the muscle tissue works together to push or pull the skeleton and move the organism conciously. For smooth muscle, the muscle tissue works together to push, pull, or constrict various structures unconciously. An example of smooth muscle is the muscles involved in pushing food through the esophagus. For cardiac muscle, the muscle tissue works together to pump the entire heart in tandem.