Which part of the digestive system is responsible for the absorption of nutrients?

The duodenum is the first part of the small intestine and plays a crucial role in the digestion and absorption of nutrients. It is where chyme from the stomach mixes with bile from the liver and digestive enzymes from the pancreas, allowing for the breakdown of food substances. The lining of the duodenum contains villi and microvilli, which increase the surface area for absorption, enabling efficient uptake of nutrients like amino acids, fatty acids, and simple sugars into the bloodstream.

In contrast, the large intestine primarily absorbs water and electrolytes, while the esophagus is mainly a conduit for food to reach the stomach, and the rectum serves as a storage area for feces before elimination. Thus, while these structures have important roles in the digestive process, the duodenum is specifically adapted for the absorption of nutrients.