Complex sentence: The pancreatic islets or islets of Langerhans are the regions of the pancreas that contain its endocrine (i.e., hormone-producing) cells, discovered in 1869 by German pathological anatomist Paul Langerhans.
Split into simpler sentences: The pancreatic islets or islets of Langerhans are the regions of the pancreas that contain its endocrine (i.e., hormone-producing) cells. Discovered in 1869 by German pathological anatomist Paul Langerhans.