Small intestine and nutrient absorption

In this talk, we turn our attention to small intestine and nutrient absorption, framing our discussion around the structure and specialized functions of the small intestine, including its three main sections, duodenum, jejunum, and ilium and their specific roles in digestion and absorption. We will explore the microscopic features that maximize nutrient uptake, such as VL and microvilli and the enzymatic processes that break down carbohydrates, proteins, and fats. Additionally, we will discuss the mechanisms of nutrient transport and the regulation of micronutrient absorption. Finally, common disorders affecting the small intestine and their impact on nutrient absorption will be highlighted. The small intestine is a specialized part of the gastrointestinal tract, responsible for most nutrient absorption. It is divided into three sections, the duodenum, jejunum, and ilium. The duodenum, the shortest segment, receives chyme from the stomach and secretions from the pancreas and liver. The jejunum absorbs most nutrients, while the ileum, the longest section, absorbs vitamin B 12, bile salts, and any remaining nutrients. The folded lining with lili and crypts maximizes surface area for absorption. At a microscopic level, the small intestine's absorptive power comes from its unique surface architecture. Finger like Vili covered in column epithelial cells lined with microvilli forming the brush border, greatly increase the absorptive area