This definitions covers Key Definitions within Glucose Regulation for GCSE Biology. Topic 6: Glucose Regulation It is section 9 of 15 in this topic. Make sure you can use the exact wording confidently, because definition marks are often lost through vague language.
Key Definitions
Blood glucose concentration: The amount of glucose dissolved in the blood plasma, normally maintained within the range of approximately 4–7 mmol/L.
Insulin: A hormone produced by beta cells in the pancreas that lowers blood glucose by causing liver and muscle cells to take up glucose and convert it to glycogen for storage.
Glucagon: A hormone produced by alpha cells in the pancreas that raises blood glucose by stimulating the liver to break down glycogen into glucose and release it into the blood.
Glycogen: A polysaccharide storage carbohydrate made from glucose; stored in liver and muscle cells; can be broken down back to glucose when blood glucose is low.
Pancreas: A gland that acts as both receptor and coordination centre for blood glucose regulation; contains alpha cells (secrete glucagon) and beta cells (secrete insulin) in the islets of Langerhans.
Type 1 diabetes: A condition in which the immune system destroys the beta cells of the pancreas, so no insulin is produced; managed with insulin injections.
Type 2 diabetes: A condition in which body cells become resistant to insulin (do not respond normally); linked to obesity and lifestyle; managed through diet, exercise, and sometimes medication.
Practice questions for Glucose Regulation
Which organ monitors blood glucose concentration and secretes insulin and glucagon?
Explain how blood glucose concentration is raised when it falls below the normal level.
Quick recall flashcards
What is glycogen and where is it stored?
Glycogen is the storage form of glucose. It is stored in the liver and in muscle cells. The liver can convert glycogen back to glucose when blood glucose falls too low.
What does insulin do when blood glucose is too high?
Insulin is released by the pancreas. It causes body cells to take up glucose from the blood, and causes the liver to convert excess glucose into glycogen for storage. Blood glucose falls.