Offshore are numerous coral reefs and tiny islets. The archipelago consists of 16 Islands and Islets. The island group are known to consist of five uninhabited islets and three barren rocks. Glipizide acts by partially blocking potassium channels among beta cells of pancreatic islets of Langerhans. The coastline consists of various beaches, bays, islets and skerries. The Funafuti Conservation Area consists of of ocean, reef, lagoon, channel and six uninhabited islets. It consists of 21 islands, islets and rocks of volcanic origin. It covers the island of Rhodes and a few uninhabited offshore islets. Insulin is synthesized and secreted in the beta cells of the islets of Langerhans. Insulin is produced by the pancreas in a region called Islets of Langerhans. There are 118 islands in French Polynesia and many more islets or "motus" around atolls. Beta cells in the islets of Langerhans release insulin in two phases. The Lord Howe Island Group comprises 28 islands, islets, and rocks. The beta cells in the pancreatic islets are sensitive to the blood glucose concentration. A large number of islands, islets, and rocks hug the coast of Crete.