Insulin is secreted by pancreatic beta cells in the islets of Langerhans.
The Source of Insulin: Pancreatic Beta Cells
The primary source of insulin within the body are specialized cells located in the pancreas. Here's a more detailed breakdown:
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Pancreas: This organ is responsible for both exocrine (enzyme secretion for digestion) and endocrine (hormone secretion) functions.
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Islets of Langerhans: Scattered throughout the pancreas are clusters of endocrine cells known as the Islets of Langerhans. These islets contain several types of cells, each producing different hormones.
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Beta Cells: Specifically, pancreatic beta cells, which reside within these islets, are the cells that synthesize and secrete insulin. These cells are highly sensitive to changes in blood glucose levels.
Regulation of Insulin Secretion
Insulin secretion is primarily regulated by the concentration of glucose in the blood. According to the provided reference, insulin is secreted in response to a rise in blood glucose concentration. When blood sugar levels increase (for example, after a meal), beta cells detect this change and release insulin into the bloodstream.
Role of Insulin
Insulin plays a crucial role in:
- Facilitating the uptake of glucose from the blood into cells for energy.
- Promoting the storage of glucose as glycogen in the liver and muscles.
- Inhibiting the production of glucose by the liver.
In essence, insulin helps to lower blood glucose levels and maintain metabolic balance.
