The document discusses homeostasis and the regulation of blood glucose levels. It explains that glucose levels are normally maintained between 5-5.5 mmol/dm3. If levels rise too high or fall too low, issues can occur. Insulin allows glucose to enter cells, while lack of insulin causes high blood sugar. Type 1 diabetes is caused by immune destruction of beta cells, while Type 2 diabetes is associated with aging and obesity. Glucose levels are regulated through a negative feedback loop involving the liver, alpha and beta cells, insulin, and glucagon.

1. Homeostasis The control of blood sugar levels (The Regulation of Glucose in the blood)

4. Insulin is the “key” that allows special “gates” for sugar transport across cell membranes to be opened

13. Normal blood sugar level

14. Normal blood sugar level

15. Normal blood sugar level If blood sugar rises This could be the Result of ingestion of Food or release of Glucose from the liver

16. Normal blood sugar level If blood sugar rises This could be the Result of ingestion of Food or release of Glucose from the liver

17. Normal blood sugar level If blood sugar rises This could be the Result of ingestion of Food or release of Glucose from the liver Detector – the alpha and beta cells of the Islets of langerhans. The alpha cells stop secreting glucagon and the beta cells secrete insulin

18. Normal blood sugar level If blood sugar rises This could be the Result of ingestion of Food or release of Glucose from the liver Detector – the alpha and beta cells of the Islets of langerhans. The alpha cells stop secreting glucagon and the beta cells secrete insulin

19. Normal blood sugar level If blood sugar rises This could be the Result of ingestion of Food or release of Glucose from the liver Detector – the alpha and beta cells of the Islets of langerhans. The alpha cells stop secreting glucagon and the beta cells secrete insulin Effector – liver cells stop breaking glycogen down due to drop in glucagon; most body cells increase uptake and use of glucose due to rise in insulin

20. Normal blood sugar level If blood sugar rises This could be the Result of ingestion of Food or release of Glucose from the liver Detector – the alpha and beta cells of the Islets of langerhans. The alpha cells stop secreting glucagon and the beta cells secrete insulin Effector – liver cells stop breaking glycogen down due to drop in glucagon; most body cells increase uptake and use of glucose due to rise in insulin

21. Normal blood sugar level If blood sugar rises This could be the Result of ingestion of Food or release of Glucose from the liver Detector – the alpha and beta cells of the Islets of langerhans. The alpha cells stop secreting glucagon and the beta cells secrete insulin Effector – liver cells stop breaking glycogen down due to drop in glucagon; most body cells increase uptake and use of glucose due to rise in insulin Blood glucose stabilised

22. Normal blood sugar level If blood sugar rises This could be the Result of ingestion of Food or release of Glucose from the liver Detector – the alpha and beta cells of the Islets of langerhans. The alpha cells stop secreting glucagon and the beta cells secrete insulin Effector – liver cells stop breaking glycogen down due to drop in glucagon; most body cells increase uptake and use of glucose due to rise in insulin Blood glucose stabilised negative feedback control loop

23. Normal blood sugar level

24. Normal blood sugar level

25. Normal blood sugar level If blood glucose falls This could be the result of a high rate of cellular uptake and use of glucose or failure to ingest carbohydrate foods

26. Normal blood sugar level If blood glucose falls This could be the result of a high rate of cellular uptake and use of glucose or failure to ingest carbohydrate foods

27. Normal blood sugar level Detector – alpha and beta cells of the Islets of Langerhans. The alpha cells secrete glucagon and the beta cells stop secreting insulin If blood glucose falls This could be the result of a high rate of cellular uptake and use of glucose or failure to ingest carbohydrate foods

28. Normal blood sugar level Detector – alpha and beta cells of the Islets of Langerhans. The alpha cells secrete glucagon and the beta cells stop secreting insulin If blood glucose falls This could be the result of a high rate of cellular uptake and use of glucose or failure to ingest carbohydrate foods

29. Normal blood sugar level Detector – alpha and beta cells of the Islets of Langerhans. The alpha cells secrete glucagon and the beta cells stop secreting insulin If blood glucose falls This could be the result of a high rate of cellular uptake and use of glucose or failure to ingest carbohydrate foods Effector – liver cells break down glycogen into glucose due to rise in glucagon: most body cells decrease uptake and use of glucose due to fall in insulin

30. Normal blood sugar level Detector – alpha and beta cells of the Islets of Langerhans. The alpha cells secrete glucagon and the beta cells stop secreting insulin If blood glucose falls This could be the result of a high rate of cellular uptake and use of glucose or failure to ingest carbohydrate foods Effector – liver cells break down glycogen into glucose due to rise in glucagon: most body cells decrease uptake and use of glucose due to fall in insulin

31. Normal blood sugar level Detector – alpha and beta cells of the Islets of Langerhans. The alpha cells secrete glucagon and the beta cells stop secreting insulin If blood glucose falls This could be the result of a high rate of cellular uptake and use of glucose or failure to ingest carbohydrate foods Effector – liver cells break down glycogen into glucose due to rise in glucagon: most body cells decrease uptake and use of glucose due to fall in insulin Blood glucose stabilised

32. Normal blood sugar level Detector – alpha and beta cells of the Islets of Langerhans. The alpha cells secrete glucagon and the beta cells stop secreting insulin If blood glucose falls This could be the result of a high rate of cellular uptake and use of glucose or failure to ingest carbohydrate foods Effector – liver cells break down glycogen into glucose due to rise in glucagon: most body cells decrease uptake and use of glucose due to fall in insulin Blood glucose stabilised negative feedback control loop