The jejunum is the midsection of the small intestine, connecting the duodenum to the ileum. It is about 2.5 m long, and contains the plicae circulares, and villi that increase its surface area. Products of digestion (sugars, amino acids, and fatty acids) are absorbed into the bloodstream here.
Not to be confused with the cells of the islets of Langerhans, found in the pancreas, or Langhans giant cell.
Located in the area of the pancreas know as the islets of Langerhans (the organâs endocrine structures), they are one of at least five different types of islet cells that produce and secrete hormones directly into the bloodstream.