What is the digestive system?

• A. System that breaks down food
• B. System that controls body functions
• C. System that removes waste
• D. System that allows movement

Answer: (A)

Digestive system breaks down food into nutrients that the body can use for energy, growth, and maintenance. It includes the mouth, esophagus, stomach, and intestines, along with organs like the liver and pancreas that produce enzymes and bile to help digestion. Mechanical actions such as chewing and stomach grinding work with chemical digestion from enzymes to turn food into small, absorbable molecules. Most nutrients are absorbed in the small intestine, while water absorption and waste processing occur later in the large intestine, leading to elimination of undigested material through the digestive tract. This focus on breaking down food and extracting usable nutrients is what sets the digestive system apart from systems that control body functions or enable movement, or from the excretory system that mainly handles waste removal. In livestock, understanding digestion helps explain how feed quality and processing affect energy and nutrient availability for growth and production.