What is the primary function of the small intestine in digestion?

The primary function of the small intestine in digestion is the absorption of nutrients. Once the food has been broken down into its constituent components—such as carbohydrates, proteins, and fats—these nutrients pass through the walls of the small intestine and enter the bloodstream. The small intestine has a large surface area due to the presence of villi and microvilli, which facilitate this nutrient absorption process.

While the small intestine does play a role in mechanical digestion through peristaltic movements and has glands that secrete digestive enzymes to aid in breaking down food, its main role is to ensure that the body can effectively absorb essential nutrients and deliver them to cells for energy, growth, and repair. Storage of food, on the other hand, is primarily the function of the stomach. Thus, the focus on nutrient absorption distinctly highlights the role of the small intestine in the overall digestive process.