Homeostasis

maintain body fluids

1. 01-Wed-2019 Muztaba khan 1 PRESENTATION ON: Homeostasis Presented by: Mohammad Muztaba Asst . Professor(Jr.) Department of Pharmacology Bhavdiya institute sibar sohawal Ayodhya

2. Homeostasis Homeostasis was defined by Claude Bernard and later by Walter Bradford Cannon in 1926,1929 and 1932. Homeostasis  is a key concept in understanding how our body works.  ' homeo ,' meaning 'similar,' and 'stasis,' meaning 'stable.  Homeostasis is the maintenance of a constant internal environment [body fluids (tissue fluid & blood) 01-Wed-2019 2 Muztaba khan

3. It is the cycle of events in which the status of the body condition is monitored, evaluated, changed, remonitored and re-evaluated. Each monitored variable, such as blood pressure, blood temperature and blood glucose, is called controlled condition. Any disruptions that change the controlled condition is called stimulus. F EEDBACK SYSTEMS 01-Wed-2019 3 Muztaba khan

4. COMPONENTS OF FEEDBACK SYSTEMS It consists of three components: Receptor Control centre Effector Receptor : It is the body structure that monitors the controlled condition and sent input to the control centre. The input is in the form of nerve impulses and chemical signals. 01-Wed-2019 4 Muztaba khan

5. Control centre: It sets the range of values within which a controlled condition should be maintained, evaluates the input it receives from the receptors, and sent output when ever needed. Output is in the form of nerve impulses, hormones, etc. Effector: It is a body structure which receives the output from the control centre and produces effect that changes the controlled condition. Nearly every organ or tissue in the body can act as effectors. 01-Wed-2019 5 Muztaba khan

6. Chapter 12 Homeostasis Homeostasis (Concept Map) 01-Wed-2019 6 Muztaba khan

7. HOMEOSTASIS The maintenance of a constant internal environment 01-Wed-2019 7 Muztaba khan

8. Principles of Homeostasis HOMEOSTASIS The maintenance of a constant internal environment 01-Wed-2019 8 Muztaba khan

9. Principles of Homeostasis S tim u l us Change in internal en v ir on m ent HOMEOSTASIS The maintenance of a constant internal environment 01-Wed-2019 9 Muztaba khan

10. Principles of Homeostasis S tim u l us Change in internal en v ir on m ent HOMEOSTASIS The maintenance of a constant internal environment Receptors Detect the change 01-Wed-2019 10 Muztaba khan

11. Principles of Homeostasis S tim u l us Change in internal en v ir on m ent HOMEOSTASIS The maintenance of a constant internal environment Receptors Detect the change Self-corrective Mechanism To rectify the change 01-Wed-2019 11 Muztaba khan

12. Principles of Homeostasis S tim u l us Change in internal en v ir on m ent HOMEOSTASIS The maintenance of a constant internal environment Receptors Detect the change Self-corrective Mechanism To rectify the change E x a m p l es Regulation of blood glucose concentration 01-Wed-2019 12 Muztaba khan

13. Principles of Homeostasis S tim u l us Change in internal en v ir on m ent HOMEOSTASIS The maintenance of a constant internal environment Receptors Detect the change Self-corrective Mechanism To rectify the change E x a m p l es Regulation of blood glucose concentration Regulation of blood water potential 01-Wed-2019 13 Muztaba khan

14. Principles of Homeostasis S tim u l us Change in internal en v ir on m ent HOMEOSTASIS The maintenance of a constant internal environment Receptors Detect the change Self-corrective Mechanism To rectify the change E x a m p l es Regulation of blood glucose concentration Regulation of blood water potential Regulation of body temperature 01-Wed-2019 14 Muztaba khan

15. Principles of Homeostasis S tim u l us Receptors Self-corrective Mechanism Negative Feedback Change in internal en v ir on m ent Detect the change Regulation of blood glucose concentration E x a m p l es 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 01-Wed-2019 15 Muztaba khan

16. TYPES OF FEED BACK SYSTEMS POSITIVE FEEDBACK It reverses a change in controlled condition. E g . What Happens When Glucose Concentration Falls? NEGATIVE FEEDBACK It strengthens or reinforces the input. Eg . Regulating Body Temperature - on a Hot Day 01-Wed-2019 16 Muztaba khan

17. Stimulus Blood glucose concentration falls below normal levels What Happens When Glucose Concentration Falls? 01-Wed-2019 17 Muztaba khan

18. Stimulus Blood glucose concentration falls below normal levels Receptor Islets of Langerhans in pancreas stimulated pancreas What Happens When Glucose Concentration Falls? 01-Wed-2019 18 Muztaba khan

19. pancreas li v er Corrective Mechanism Islets of Langerhans secretes more glucagon, which is transported by blood to liver and muscles Stimulus Blood glucose concentration falls below normal levels Receptor Islets of Langerhans in pancreas stimulated What Happens When Glucose Concentration Falls? 01-Wed-2019 19 Muztaba khan

20. Stimulus Blood glucose concentration falls below normal levels li v er glycogen  glucose Receptor Islets of Langerhans in pancreas stimulated What Happens When Glucose Concentration Falls? Corrective Mechanism Islets of Langerhans secretes more glucagon, which is transported by blood to liver and muscles Glucagon converts stored glycogen back to glucose. From liver, glucose enters bloodstream pancreas 01-Wed-2019 20 Muztaba khan

21. Stimulus Blood glucose concentration falls below normal levels li v er glycogen  glucose Receptor Islets of Langerhans in pancreas stimulated Blood glucose concentration rises and glucagon production decreases What Happens When Glucose Concentration Falls? Corrective Mechanism Islets of Langerhans secretes more glucagon, which is transported by blood to liver and muscles Glucagon converts stored glycogen back to glucose. From liver, glucose enters bloodstream pancreas 01-Wed-2019 21 Muztaba khan

22. Stimulus Blood glucose concentration falls below normal levels li v er glycogen  glucose Receptor Islets of Langerhans in pancreas stimulated Blood glucose concentration rises and glucagon production decreases Blood glucose concentration returns to normal What Happens When Glucose Concentration Falls? Corrective Mechanism Islets of Langerhans secretes more glucagon, which is transported by blood to liver and muscles Glucagon converts stored glycogen back to glucose. From liver, glucose enters bloodstream pancreas 01-Wed-2019 22 Muztaba khan

23. li v er Receptor Islets of Langerhans in pancreas stimulated Positive feedback Stimulus Blood glucose concentration falls below normal levels Blood glucose concentration returns to normal What Happens When Glucose Concentration Falls? Blood glucose concentration rises and glucagon pr oduction decreases glycogen  glucose Corrective Mechanism Islets of Langerhans secretes more glucagon, which is transported by blood to liver and muscles Glucagon converts stored glycogen back to glucose. From liver, glucose enters bloodstream pancreas 01-Wed-2019 23 Muztaba khan

24. Chapter 1 Homeostasis Regulating Body Temperature - on a Hot Day Positive feed back 01-Wed-2019 24 Muztaba khan

25. Stimulus Blood and skin temperatures rise Regulating Body Temperature - on a Hot Day 01-Wed-2019 25 Muztaba khan

26. 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 01-Wed-2019 26 Muztaba khan

27. Stimulus Blood and skin temperatures rise hair follicle ha i r a rt e ri o l e blood capillaries erector muscle 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 01-Wed-2019 27 Muztaba khan

28. 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 capillaries skin surface Arterioles in skin dilate 1 More blood flows to capillaries in skin arteriole 2 3 4 Greater heat loss Shunt vessels constrict Regulating Body Temperature - on a Hot Day 01-Wed-2019 28 Muztaba khan

29. Stimulus Blood and skin temperatures rise Hypothalamus of brain is stimulated and sends nerve impulses to relevant body parts sweat duct sweat pore sweat gland Sweat glands more active Sweat produc t ion 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 01-Wed-2019 29 Muztaba khan

30. Stimulus Blood and skin temperatures rise Hair erector muscles in skin relax erector muscle hair follicle ha i r a rt e ri o l e blood capillaries 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 01-Wed-2019 30 Muztaba khan

31. 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 01-Wed-2019 31 Muztaba khan

32. 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 01-Wed-2019 32 Muztaba khan

33. 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 01-Wed-2019 33 Muztaba khan

34. 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 N ega t i ve f e e d back Decreased metabolic rate reduces heat production Regulating Body Temperature - on a Hot Day 01-Wed-2019 34 Muztaba khan

35. Any question….? 01-Wed-2019 35 Muztaba khan