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Where are the islets of Langerhans located in the pancreas?
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human endocrine system
The principal glands of the female and male human endocrine systems.
The islets of Langerhans are located within the pancreas of most vertebrates. They exist as irregularly shaped patches of endocrine tissue distributed throughout the organ. In the normal human pancreas, there are approximately 1 million of these islets.1
While the endocrine cells of all tetrapods are organized into these distinct islets, the evolutionary history of this structure varies; for instance, in primitive fishes, the hormone-secreting cells are scattered within the wall of the intestine rather than being contained within a discrete pancreas.2