BRAINCAKEGlucagon
Insulin and glucagon are antagonistic hormones. Glucagon is produced by the alpha cells of the islets of Langerhans in response to a low blood sugar concentration. The only cells that have glucagon receptors are liver cells and fat cells. Glucagon raises the blood glucose concentration by breaking down glycogen in the liver (glycogenolysis), reducing the amount of glucose absorbed by liver cells and increasing gluconeogenesis.
Sign in free to see the rest of this lesson, the R.E.C.I.P.E. recall steps and the quiz
BrainCake is free. Make an account in seconds and pick up where this page stops.
Key terms in this lesson
- Hormone
- A chemical messenger, secreted directly into the blood by an endocrine gland, that travels to target cells and alters their activity.
- Glycogenolysis
- The breakdown of glycogen to glucose, occurring mainly in the liver in response to glucagon or adrenaline.
- Gluconeogenesis
- The production of glucose from non-carbohydrate sources such as amino acids and fatty acids.
- Islets of Langerhans
- Groups of endocrine cells in the pancreas containing alpha cells, which secrete glucagon, and beta cells, which secrete insulin.
- Insulin
- A hormone secreted by beta cells of the islets of Langerhans in response to high blood glucose concentration that increases the uptake of glucose by cells.
More in Hormonal Communication
- The Adrenal Glands
- Adrenal Cortex
- Adrenal Medulla
- Pancreas
- Blood glucose concentration
- Insulin
- Mechanism of Insulin Secretion
- Diabetes Mellitus
All 11 lessons in Hormonal Communication · All OCR A-level Biology topics