What are the main functions of the small intestine in the digestion process?

The small intestine plays key roles in the digestion process. Its main functions include enzymatic digestion, nutrient absorption, and secretion of digestive juices. Enzymes from the pancreas and intestinal wall break down complex molecules into simpler forms. Villi and microvilli on the intestinal lining increase the absorptive surface, facilitating the uptake of nutrients, including amino acids, fatty acids, and sugars. The small intestine also secretes mucus for lubrication and protection. Through peristalsis, the chyme undergoes thorough mixing and absorption in the small intestine, ensuring the extraction of essential nutrients and contributing to the final stages of digestion before reaching the large intestine.