The jejunum is the middle section of the small intestine, located between the duodenum and the ileum. It plays a key role in the digestion and absorption of nutrients, particularly carbohydrates and proteins. The inner lining of the jejunum contains numerous folds, villi, and microvilli that increase surface area to efficiently absorb nutrients into the bloodstream. Proper function of the jejunum is essential for maintaining overall nutritional health.