3. 19 Homeostasis 19.1 Homeostasis 19.2 The urinary system 19.3 The kidney 19.4 The functions of the kidney 19.5 Regulation of body temperature 19.6 The structure and functions of the skin 19.7 How do mammals control their body temperature? 19.8 Regulation of glucose level in blood Mind Map

4. 19.1 Homeostasis

5. Normal value e.g. 37 o C body temperature Rise above normal value e.g. 40 o C body temperature Fall below normal value e.g. 35 o C body temperature Correction mechanism Normal value e.g. 37 o C body temperature Correction mechanism Negative feedback mechanism 19.1 Homeostasis

6. by kidneys by skin by liver & pancreas by kidneys Constant internal environment Water content Salt content Body temperature Blood glucose level 1 1 2 2 3 3 4 4 19.1 Homeostasis

7. 19.2 The urinary system

8. aorta renal artery left kidney ureters urinary bladder urethra Inferior vena cava renal vein right kidney sphincter muscle 19.2 The urinary system

9. produce urine Kidneys 1 from kidneys to urinary bladder carry urine Ureters 2 temporary storage of urine Urinary bladder 3 1122 3 19.2 The urinary system

10. usually tightly contracts so that urine cannot get out sphincter muscle 19.2 The urinary system

11. Urination sphincter muscle urinary bladder urethra when it is full 1 relaxes 2 urine is discharged through urethra 3 19.2 The urinary system

12. Structure Functions Kidneys Osmoregulation Excretion Ureter Carry urine from kidneys to urinary bladder Temporary stores urine Discharges urine Urinary bladder Urethra Summary 19.2 The urinary system

13. 1.Study a human torso or a dissected mammal (e.g. rat) showing the urinary system. 2.Identify the following parts: kidney, ureter, urinary bladder and urethra. Experiment 19.1 To examine the urinary system of a human torso or a dissected mammal 19.2 The urinary system

14. 19.3 The kidney

15. cortex medulla pelvis nephron Structure of kidney 19.3 The kidney

16. Structure of kidney Kidney is made up of about a million nephrons Nephron is the basic unit of kidney nephron 19.3 The kidney

17. Bowman’s capsule first convolution loop of Henle second convolution collecting duct 1 432 5 1 + 2 + 3 + 4 + 5 = nephron 19.3 The kidney

18. afferent arteriole glomerulus efferent arteriole renal venule capillary 35 4 4 21 19.3 The kidney

19. 1.Study a kidney model or the longitudinal section of a dissected mammalian kidney. 2.Try to identify the following parts: cortex, medulla, pelvis, ureter, renal artery and renal vein. Experiment 19.2 To examine a kidney model or the longitudinal section of a dissected mammalian kidney. 19.3 The kidney

21. afferent arteriole efferent arteriole with larger diameter with smaller diameter 1. Ultrafiltration Increase in hydrostatic pressure in glomerulus 19.3 The kidney

22. When the blood passes into glomerulus, This liquid is called glomerular filtrate due to high hydrostatic pressure plasma proteins & blood cells Except: Bowman’s capsular space through wall of glomerulus into all the substances in the blood are forced out 19.3 The kidney

23. through the walls of glomerulus & Bowman’s capsule high blood pressure forces small molecules high blood pressure forces small molecules into the capsular space is a process that 19.3 The kidney

24. Glomerular filtrate passes through the tubule Glucose Amino acids All blood capillaries around tubule are reabsorbed into Most of water Some salts 2. Reabsorption 19.3 The kidney

25. Reabsorption of these useful substances (except water) takes place by diffusion & active transport Water is reabsorbed by osmosis Glomerular filtrate urine excess mineral saltswaterurea 2. Reabsorption contains 19.3 The kidney

26. all glucose & amino acids, most of water & some salts are retaken back into capillaries all glucose & amino acids, most of water & some salts are retaken back into capillaries is a process that by diffusion, active transport & osmosis by diffusion, active transport & osmosis 19.3 The kidney

27. 19.4 The functions of the kidney

28. the correct level of water in the body the correct level of water in the body is the maintenance of Keeps the water level constant 19.4 The functions of the kidney

29. a smaller volume of conc. urine is produced a larger proportion of water is reabsorbed a larger volume of dilute urine is produced more urine with a high conc. of salt is produced extra water is lost with the excretion of excess salts after drinking a lot of water a smaller proportion of water is reabsorbed concentrated blood higher salt conc. in blood 1 after sweating 2 after eating a salty meal 3 Normal water content in blood dilute blood 19.4 The functions of the kidney

30. is a process to remove metabolic wastes 19.4 The functions of the kidney

31. Liver 2 Skin 1 Excretory organs excretes urea and other salts in the sweat excrete carbon dioxide Lungs 3 excrete bile pigments excrete urea Kidneys 4 19.4 The functions of the kidney

32. Liver 2 Excretory organs transport to excess amino acid cannot be stored nitrogenous waste Deamination urea 19.4 The functions of the kidney

33. Regulation of 19.5 Regulation of body temperature

34. Balance heat loss heat gain maintain a suitable body temperature Poikilotherms (cold-blooded animals) Homoiotherms (warm-blooded animals) According to stability of body temperature, two groups of animals 19.5 Regulation of body temperature

35. Little control over their body temperatures Their body temperatures vary with that of the surroundings fish invertebrates reptiles amphibians Poikilotherms (cold-blooded animals) 19.5 Regulation of body temperature

36. Their body temperature can be kept constant irrespective of their environment birds mammals Homoiotherms (warm-blooded animals) 19.5 Regulation of body temperature

37. The Structure & Functions of 19.6 The structure and functions of the skin

38. How many layers in the skin? Two layers epidermis dermis epidermis 19.6 The structure and functions of the skin

39. How many layers in the epidermis? Three layers Outermost layer Middle layer Epidermis Innermost layer 19.6 The structure and functions of the skin

40. reduce water loss 3 Outermost layer dead cells protect the body against mechanical injury prevent the entry of bacteria 1 2 19.6 The structure and functions of the skin

41. Epidermis become dead while approaching the surface Middle layer Outermost layer Middle layer living cells 19.6 The structure and functions of the skin

42. produce new cells by mitosis 1 Innermost layers Innermost layer 19.6 The structure and functions of the skin

43. Innermost layers Black pigments UV light UV light UV light Protect cells from deeper layers Innermost layer Absorb UV light 2 Melanin 19.6 The structure and functions of the skin

44. epidermis dermis 19.6 The structure and functions of the skin

45. blood vessel Regulation of body temperature Material exchange Heat loss 2 1 19.6 The structure and functions of the skin

46. sweat pore sweat duct sweat gland secrete sweat cooling excretion 19.6 The structure and functions of the skin

47. produces hair contracts to raise hair during cold conditions reduces heat loss and assists in temperature regulation hair erector muscle hair follicle 19.6 The structure and functions of the skin

48. sebaceous gland secrete sebum keeps the skin water- proof kills micro- organisms 19.6 The structure and functions of the skin

49. receptors detect pain pressure touch temperature 19.6 The structure and functions of the skin

50. Experiment 19.3 Examine a skin model or a selection of the mammalian skin 1.Study the model of the mammalian skin. ( OR: Study a preserved slide of mammalian skin. Observe it under the microscope. ) 2.Identify the structure of the mammalian skin. Study how each structure works. 19.6 The structure and functions of the skin

51. Experiment 19.3 Examine a skin model or a selection of the mammalian skin 19.6 The structure and functions of the skin

52. How do mammals control their 19.7 How do mammals control their body temperature? ?

53. Body temp. 37 o C Body temperature 37 o C Environmental temperature 25 o C Heat Loss Heat Production General idea of thermoregulation 19.7 How do mammals control their body temperature?

54. of organism from environment from organism to environment Balance Radiation Convection Conduction Evaporation Heat Loss Heat Gain Respiration Conduction 19.7 How do mammals control their body temperature?

55. What happens when the body is hot? sweat heat loss through the skin evaporation of sweat absorbs heat from skin surface 19.7 How do mammals control their body temperature?

56. as more sweat evaporates,more heat is absorbed more heat is lost What happens when the body is hot? more sweat is produced 19.7 How do mammals control their body temperature?

57. sweat heat loss through the skin by evaporation of sweat becomes ineffective evaporation of sweat becomes difficult What happens when the body is under hot and humid condition? 19.7 How do mammals control their body temperature?

58. cell Respiration Heat blood Heat Loss by radiation convection, conduction Heat production  Body temperature can be kept normal skin (body surface) 37 o C (body) 25 o C (surrounding) 19.7 How do mammals control their body temperature?

59. Vasodilation artery Skin arteriole dilates more warm blood carried to the superficial blood capillaries vein More Heat Loss skin Skin temperature 19.7 How do mammals control their body temperature? blood

60. reduces the thickness of air trapped Hair lie flat heat loss increases erector muscles relax 19.7 How do mammals control their body temperature?

61. Vasodilation Erector muscle relaxes More Sweating brings more blood to the skin hairs lie downheat loss by evaporation of sweat increases By more heat loss by Radiation Convection Conduction less heat is trapped Actions for increasing heat loss 19.7 How do mammals control their body temperature?

62. Erector Muscle contracts Less Sweating brings less blood to the skin hairs raise upheat loss by evaporation of sweat decreases By reduce heat loss by Radiation Convection Conduction more heat is trapped Actions for decreasing heat loss 19.7 How do mammals control their body temperature? Vasodilation

63. What happens when the body is cold? Long-term response A thicker layer of subcutaneous fat & thicker fur are developed Heat loss reduced 19.7 How do mammals control their body temperature?

64. What happens when the body is hot? Long-term response Some mammals develop a thinner layer of subcutaneous fat and shed their fur Heat loss increased 19.7 How do mammals control their body temperature?

65. 19.8 Regulation of glucose level in blood in Blood

66. 19.8 Regulation of glucose level in blood blood glucose level High stimulates secretes more insulin Pancreas and less glucagon

67. 19.8 Regulation of glucose level in blood Glucose Glycogen Blood Glucose High Blood Glucose Normal How ? Insulin promotes this action Liver

68. secretes more insulin and less glucagon stimulates 19.8 Regulation of glucose level in blood Pancreas blood glucose High Liver High Blood Glucose Insulin Normal Blood Glucose Excess glucose Glycogen

69. secretes more insulin and less glucagon 19.8 Regulation of glucose level in blood Kidneys cannot reabsorb all glucose Diabetes mellitus urine with glucose stimulates Pancreas blood glucose High Liver High Blood Glucose Insulin Normal Blood Glucose Excess glucose Glycogen

70. lower blood glucose level more insulin and less glucagon is secreted absorbs more glucose in liver converts excess glucose to glycogen some glucose are excreted in urine Diabetes mellitus 19.8 Regulation of glucose level in blood liverhigh blood glucose is keptand higher than the reabsorption capacity in kidney tubules not enough insulin is secreted detected by pancreas blood glucose concentration

71. Mind Map Homeostasis includes osmoregulationregulation of blood glucose level regulation of body temperature constant internal environment is the maintenance of negative feedback mechanism which is usually controlled by

72. osmoregulation ultrafiltration nephrons excretion urination reabsorption larger proportion of water is reabsorbed kidneys smaller proportion of water is reabsorbed controlled by also for which is made up of two processes involved after drinking a lot of water after sweating urea is removed by Mind Map

73. controlled by regulation of body temperature skin 1. secret more sweat 2. vasodilation 4. hairs lie flat 3. erector muscles relax 5. thinner subcutaneous fat 1. secret less sweat 4. hairs pulled erect 5. thicker subcutaneous fat 2. vasoconstriction 3. erector muscles contract hot condition cold condition Mind Map

74. high blood glucose level low blood glucose level regulation of blood glucose level pancreas secretes more insulin but less glucagon pancreas secretes more glucagon but less insulin liver converts glucose to glycogen liver converts glycogen to glucose Mind Map