False-colour scanning electron micrograph (SEM) of acini cells of the pancreas. The pancreas is a major digestive gland, secreting both exocrine (digestive enzyme) & endocrine (insulin & glucagon hormone) products. The cells here are arranged in serous acini or clusters and produce exocrine secretions. Some cells (with red dots) are more actively secreting than others. Their enzyme pro- ducts drain into a highly branched system of ducts of increasing size, that terminates in the main pancreatic duct, which feeds into the duodenum. A smaller proportion of cells (here hidden) secrete hormones. Magnification: x260 at 6x7cm size. Magnification: x420 at 4x5 inch size.