The endocrine system V Flashcards
Which organs require glucose exclusively as a source of energy?
Brain and retina
What is glucose homeostasis?
The maintenance of constant glucose levels
Which two hormones are involved in glucose homeostasis?
Insulin and glucagon
What are the two hormonal functions of the pancreas?
Exocrine and endocrine
What is the exocrine function of the pancreas?
secretion of pancreatic enzymes for food digestion in the duodenum
What is the endocrine function of the pancreas?
Secretion of insulin and glucagon
Which part of the pancreas is responsible for hormone secretion?
Pancreatic islets of langerhans
What do the alpha cells of the pancreatic islets of langerhans secrete?
Glucagon
What do the beta cells of the pancreatic islets of langerhans secrete?
Insulin
What do the delta cells of the pancreatic islets of langerhans secrete?
Somatostasin
What do the F cells of the pancreatic islets of langerhans secrete?
Pancreatic polypeptide
Role of somatostatin?
Inhibits the release of pancreatic hormones
What do the epsilon cells of the pancreatic islets of langerhans secrete?
ghrelin
What is the function of insulin?
Decreases blood glucose levels
How does insulin decrease blood glucose levels?
Lipogenesis, glycogenesis, increases glucose uptake and storage in the liver and decreases hepatic glucose production
What is lipogenesis?
The synthesis of fatty acids from non-lipid precursors
What is glycogenesis?
Conversion of glucose to glycogen for storage
What is lipolysis?
Triglyceride breakdown
Where does glucagon mainly act?
On the liver
Role of glucagon?
Increases blood glucose concentration
How does glucagon raise the BGC?
Promotes glycogenolysis and stimulates gluconeogenesis
What is glycogenolysis?
Breakdown of glycogen
What is gluconeogenesis?
Production of glucose from AAs and glycerol in the liver
