The primary function of the digestive system is to break down food into nutrients that the body can absorb and utilize for energy, growth, and repair. It begins in the mouth, where food is mechanically broken down by chewing and mixed with saliva containing enzymes. The system continues through the esophagus to the stomach, where acids and enzymes further digest the food. In the small intestine, nutrients are absorbed into the bloodstream, while the remaining undigested material progresses to the large intestine for water absorption and eventual elimination. Thus, the digestive system plays a crucial role in overall health and nutrition.