1. Chapter 12 Homeostasis

11. Fig. 12.2

13. Chapter 12 Homeostasis What Happens When Glucose Concentration Rises? January 11, 2010

14. What Happens When Glucose Concentration Rises? Stimulus Blood glucose concentration rises above normal levels January 11, 2010 Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd.

15. What Happens When Glucose Concentration Rises? Receptor Islets of Langerhans in pancreas stimulated pancreas Stimulus Blood glucose concentration rises above normal levels January 11, 2010 Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd.

16. What Happens When Glucose Concentration Rises? Receptor Islets of Langerhans in pancreas stimulated Corrective Mechanism Islets of Langerhans secretes more insulin, which is transported by blood to liver and muscles pancreas liver Stimulus Blood glucose concentration rises above normal levels January 11, 2010 Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd.

17. What Happens When Glucose Concentration Rises? Receptor Islets of Langerhans in pancreas stimulated Permeability of cell surface membrane to glucose increases Corrective Mechanism Islets of Langerhans secretes more insulin, which is transported by blood to liver and muscles pancreas liver Stimulus Blood glucose concentration rises above normal levels January 11, 2010 Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd.

18. What Happens When Glucose Concentration Rises? Receptor Islets of Langerhans in pancreas stimulated Permeability of cell surface membrane to glucose increases Corrective Mechanism Islets of Langerhans secretes more insulin, which is transported by blood to liver and muscles Liver and muscles convert excess glucose to glycogen. Glycogen is stored in liver and muscles pancreas excess glucose  glycogen liver Stimulus Blood glucose concentration rises above normal levels January 11, 2010 Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd.

19. What Happens When Glucose Concentration Rises? Receptor Islets of Langerhans in pancreas stimulated Permeability of cell surface membrane to glucose increases Corrective Mechanism Islets of Langerhans secretes more insulin, which is transported by blood to liver and muscles Liver and muscles convert excess glucose to glycogen. Glycogen is stored in liver and muscles Blood glucose concentration decreases and insulin production falls pancreas excess glucose  glycogen liver Stimulus Blood glucose concentration rises above normal levels January 11, 2010 Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd.

22. Chapter 12 Homeostasis What Happens When Glucose Concentration Falls? January 11, 2010

23. What Happens When Glucose Concentration Falls? January 11, 2010 Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd. Stimulus Blood glucose concentration falls below normal levels

24. What Happens When Glucose Concentration Falls? January 11, 2010 Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd. Receptor Islets of Langerhans in pancreas stimulated Stimulus Blood glucose concentration falls below normal levels pancreas

25. What Happens When Glucose Concentration Falls? January 11, 2010 Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd. Stimulus Blood glucose concentration falls below normal levels pancreas liver Corrective Mechanism Islets of Langerhans secretes more glucagon, which is transported by blood to liver and muscles Receptor Islets of Langerhans in pancreas stimulated

26. What Happens When Glucose Concentration Falls? January 11, 2010 Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd. Glucagon converts stored glycogen back to glucose. From liver, glucose enters bloodstream Stimulus Blood glucose concentration falls below normal levels pancreas liver glycogen  glucose Corrective Mechanism Islets of Langerhans secretes more glucagon, which is transported by blood to liver and muscles Receptor Islets of Langerhans in pancreas stimulated

27. What Happens When Glucose Concentration Falls? January 11, 2010 Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd. Glucagon converts stored glycogen back to glucose. From liver, glucose enters bloodstream Stimulus Blood glucose concentration falls below normal levels pancreas liver glycogen  glucose Receptor Islets of Langerhans in pancreas stimulated Corrective Mechanism Islets of Langerhans secretes more glucagon, which is transported by blood to liver and muscles Blood glucose concentration rises and glucagon production decreases

28. What Happens When Glucose Concentration Falls? January 11, 2010 Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd. Glucagon converts stored glycogen back to glucose. From liver, glucose enters bloodstream Stimulus Blood glucose concentration falls below normal levels pancreas liver glycogen  glucose Receptor Islets of Langerhans in pancreas stimulated Corrective Mechanism Islets of Langerhans secretes more glucagon, which is transported by blood to liver and muscles Blood glucose concentration rises and glucagon production decreases Blood glucose concentration returns to normal

29. What Happens When Glucose Concentration Falls? liver Receptor Islets of Langerhans in pancreas stimulated Glucagon converts stored glycogen back to glucose. From liver, glucose enters bloodstream Corrective Mechanism Islets of Langerhans secretes more glucagon, which is transported by blood to liver and muscles Negative feedback Stimulus Blood glucose concentration falls below normal levels Blood glucose concentration returns to normal January 11, 2010 Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd. Blood glucose concentration rises and glucagon production decreases glycogen  glucose pancreas

37. Chapter 12 Homeostasis Regulating Body Temperature - on a Hot Day January 11, 2010

38. January 11, 2010 Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd. Stimulus Blood and skin temperatures rise Regulating Body Temperature - on a Hot Day

39. January 11, 2010 Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd. Stimulus Blood and skin temperatures rise Receptor Temperature receptors detect changes and send nerve impulses to the brain Regulating Body Temperature - on a Hot Day

40. January 11, 2010 Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd. Stimulus Blood and skin temperatures rise Receptor Temperature receptors detect changes and send nerve impulses to the brain Hypothalamus of brain is stimulated and sends nerve impulses to relevant body parts Regulating Body Temperature - on a Hot Day blood capillaries hair follicle hair arteriole erector muscle

41. January 11, 2010 Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd. Stimulus Blood and skin temperatures rise Receptor Temperature receptors detect changes and send nerve impulses to the brain Hypothalamus of brain is stimulated and sends nerve impulses to relevant body parts Arterioles in skin dilate 1 More blood flows to capillaries in skin 2 3 Greater heat loss 4 Shunt vessels constrict Regulating Body Temperature - on a Hot Day arteriole capillaries skin surface

42. January 11, 2010 Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd. Stimulus Blood and skin temperatures rise Hypothalamus of brain is stimulated and sends nerve impulses to relevant body parts Sweat glands more active Sweat production increases More latent heat lost as sweat evaporates 6 7 5 Regulating Body Temperature - on a Hot Day Receptor Temperature receptors detect changes and send nerve impulses to the brain sweat duct sweat pore sweat gland

43. January 11, 2010 Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd. Stimulus Blood and skin temperatures rise Hair erector muscles in skin relax 8 Receptor Temperature receptors detect changes and send nerve impulses to the brain Hypothalamus of brain is stimulated and sends nerve impulses to relevant body parts Regulating Body Temperature - on a Hot Day erector muscle blood capillaries hair follicle hair arteriole

44. January 11, 2010 Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd. Stimulus Blood and skin temperatures rise Receptor Temperature receptors detect changes and send nerve impulses to the brain Hypothalamus of brain is stimulated and sends nerve impulses to relevant body parts Corrective Mechanism Increase in heat loss and decrease in heat production Regulating Body Temperature - on a Hot Day

45. January 11, 2010 Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd. Stimulus Blood and skin temperatures rise Receptor Temperature receptors detect changes and send nerve impulses to the brain Hypothalamus of brain is stimulated and sends nerve impulses to relevant body parts Corrective Mechanism Increase in heat loss and decrease in heat production Decreased metabolic rate reduces heat production Regulating Body Temperature - on a Hot Day

46. January 11, 2010 Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd. Stimulus Blood and skin temperatures rise Receptor Temperature receptors detect changes and send nerve impulses to the brain Hypothalamus of brain is stimulated and sends nerve impulses to relevant body parts Corrective Mechanism Increase in heat loss and decrease in heat production Blood temperature returns to normal levels Decreased metabolic rate reduces heat production Regulating Body Temperature - on a Hot Day

47. January 11, 2010 Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd. Stimulus Blood and skin temperatures rise Receptor Temperature receptors detect changes and send nerve impulses to the brain Hypothalamus of brain is stimulated and sends nerve impulses to relevant body parts Corrective Mechanism Increase in heat loss and decrease in heat production Blood temperature returns to normal levels Negative feedback Decreased metabolic rate reduces heat production Regulating Body Temperature - on a Hot Day

48. Regulating Body Temperature - on a Cold Day Chapter 12 Homeostasis January 11, 2010

49. Regulating Body Temperature - on a Cold Day January 11, 2010 Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd. Stimulus Blood and skin temperatures fall

50. Regulating Body Temperature - on a Cold Day January 11, 2010 Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd. Stimulus Blood and skin temperatures fall Receptor Temperature receptors detect changes and send nerve impulses to the brain

51. Regulating Body Temperature - on a Cold Day January 11, 2010 Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd. Stimulus Blood and skin temperatures fall Receptor Temperature receptors detect changes and send nerve impulses to the brain Hypothalamus of brain is stimulated and sends nerve impulses to relevant body parts blood capillaries arteriole hair hair follicle erector muscles

52. Regulating Body Temperature - on a Cold Day January 11, 2010 Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd. Stimulus Blood and skin temperatures fall Receptor Temperature receptors detect changes and send nerve impulses to the brain Less blood flows to capillaries in skin Arterioles in skin constrict Shunt vessels dilate 1 2 3 Less heat loss 4 Hypothalamus of brain is stimulated and sends nerve impulses to relevant body parts skin surface capillaries arteriole

53. Regulating Body Temperature - on a Cold Day January 11, 2010 Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd. Sweat glands less active Sweat production decreases Less latent heat lost Stimulus Blood and skin temperatures fall Receptor Temperature receptors detect changes and send nerve impulses to the brain Hypothalamus of brain is stimulated and sends nerve impulses to relevant body parts 5 6 7 sweat pore sweat duct sweat gland

54. Regulating Body Temperature - on a Cold Day Hair erector muscles in skin contract January 11, 2010 Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd. Stimulus Blood and skin temperatures fall Receptor Temperature receptors detect changes and send nerve impulses to the brain Hypothalamus of brain is stimulated and sends nerve impulses to relevant body parts 8 erector muscles blood capillaries arteriole hair hair follicle

55. Regulating Body Temperature - on a Cold Day January 11, 2010 Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd. Shivering occurs when insufficient heat is produced Stimulus Blood and skin temperatures fall Receptor Temperature receptors detect changes and send nerve impulses to the brain Hypothalamus of brain is stimulated and sends nerve impulses to relevant body parts Corrective Mechanism Decrease in heat loss and increase in heat production

56. Regulating Body Temperature - on a Cold Day January 11, 2010 Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd. Stimulus Blood and skin temperatures fall Receptor Temperature receptors detect changes and send nerve impulses to the brain Corrective Mechanism Decrease in heat loss and increase in heat production Increased metabolic rate increases heat production Hypothalamus of brain is stimulated and sends nerve impulses to relevant body parts

57. Regulating Body Temperature - on a Cold Day January 11, 2010 Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd. Blood temperature returns to normal levels Stimulus Blood and skin temperatures fall Receptor Temperature receptors detect changes and send nerve impulses to the brain Corrective Mechanism Decrease in heat loss and increase in heat production Increased metabolic rate increases heat production Hypothalamus of brain is stimulated and sends nerve impulses to relevant body parts

58. Regulating Body Temperature - on a Cold Day Corrective Mechanism Decrease in heat loss and increase in heat production Increased metabolic rate increases heat production Blood temperature returns to normal levels Negative feedback January 11, 2010 Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd. Stimulus Blood and skin temperatures fall Receptor Temperature receptors detect changes and send nerve impulses to the brain Hypothalamus of brain is stimulated and sends nerve impulses to relevant body parts

62. Chapter 12 Homeostasis Homeostasis (Concept Map) January 11, 2010

63. January 11, 2010 Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd. HOMEOSTASIS The maintenance of a constant internal environment

64. January 11, 2010 Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd. Principles of Homeostasis HOMEOSTASIS The maintenance of a constant internal environment

65. Principles of Homeostasis Stimulus Change in internal environment HOMEOSTASIS The maintenance of a constant internal environment January 11, 2010 Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd.

66. Principles of Homeostasis Stimulus Change in internal environment HOMEOSTASIS The maintenance of a constant internal environment January 11, 2010 Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd. Receptors Detect the change

67. Principles of Homeostasis Stimulus Change in internal environment HOMEOSTASIS The maintenance of a constant internal environment January 11, 2010 Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd. Receptors Detect the change Self-corrective Mechanism To rectify the change

68. Principles of Homeostasis Stimulus Change in internal environment HOMEOSTASIS The maintenance of a constant internal environment January 11, 2010 Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd. Receptors Detect the change Self-corrective Mechanism To rectify the change Examples Regulation of blood glucose concentration

69. Principles of Homeostasis Stimulus Change in internal environment HOMEOSTASIS The maintenance of a constant internal environment January 11, 2010 Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd. Receptors Detect the change Self-corrective Mechanism To rectify the change Examples Regulation of blood glucose concentration Regulation of blood water potential

70. Principles of Homeostasis Stimulus Change in internal environment HOMEOSTASIS The maintenance of a constant internal environment January 11, 2010 Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd. Receptors Detect the change Self-corrective Mechanism To rectify the change Examples Regulation of blood glucose concentration Regulation of blood water potential Regulation of body temperature

71. January 11, 2010 Copyright © 2006-2011 Marshall Cavendish International (Singapore) Pte. Ltd. Principles of Homeostasis Stimulus Receptors Self-corrective Mechanism Negative Feedback Change in internal environment Detect the change Regulation of blood glucose concentration Examples To rectify the change Regulation of blood water potential Regulation of body temperature The reverse effect of the change HOMEOSTASIS The maintenance of a constant internal environment