The term for the breakdown of food substances in the body is termed digestion. This complex process involves mechanical and chemical processes that transform food into nutrients. Through mechanical action, food is physically broken down into smaller pieces, while enzymes and acids chemically convert it into absorbable molecules. Digestion occurs in various organs throughout the digestive system, including the mouth, stomach, and intestines. Proper digestion is crucial for nutrient absorption, energy production, and overall health maintenance in living organisms.