What key processes occur in the small intestine?

The small intestine is a crucial part of the digestive system where both digestion and absorption of nutrients occur. This section of the gastrointestinal tract is specifically designed to complete the digestion of food that began in the stomach and to absorb the resulting nutrients into the bloodstream.

During the digestive process in the small intestine, enzymes from the pancreas and bile from the liver further break down carbohydrates, proteins, and fats. The inner lining of the small intestine is equipped with tiny projections called villi and microvilli that significantly increase the surface area for absorption. This enhances the small intestine’s ability to absorb essential nutrients such as vitamins, minerals, amino acids, and fatty acids, which are then transported to various parts of the body to be used for energy, growth, and repair.

While other processes, like the excretion of waste, occur in the digestive system, they primarily take place in the large intestine. Storage of nutrients primarily happens in the liver and fat tissues rather than in the small intestine. Therefore, the primary function of the small intestine centers on digestion and absorption, making that the key reason why this answer is the most accurate representation of what occurs in the small intestine.