The function of the digestive system is digestion and absorption. Digestion is the breakdown of food into small molecules, which are then absorbed into the body. The digestive system is divided into two major parts: The digestive tract (alimentary canal) is a continuous tube with two openings: the mouth and the anus.
The direct source of energy to move the sailboat is probably wind, since wind is what pushes the sail of the sailboat, which is what propels the sailboat forward.
