The answer is energy, I think
In much of a digestive tract such as the human gastrointestinal tract, smooth muscle tissue contracts in sequence to produce a peristaltic wave, which propels a ball of food (called a bolus while in the esophagus and upper gastrointestinal tract and chyme in the stomach) along the tract.
It would be a heterotroph and a omnivore because it eats grains and meats and a heterotroph because it has to get food.