说明教案课件chapter09homeostasi active regulation of internal states1

1、Chapter 9：Homeostasi：Active Regulation of Internal States 主讲：潘晓红主讲：潘晓红 华东师范大学华东师范大学 心理与认知科学学院心理与认知科学学院 Biological Psychology 1.1.HomeostasisHomeostasis Maintains Internal States Maintains Internal States within a Critical Rangewithin a Critical Range WarmthWarmth waterwater FoodFood These systems sh

2、ow redundancy are monitored by more than one mechanism. This redundancy helps keep us alive, but it also makes it difficult for us to figure out how the body regulates temperature, water balance, and food intake. Systems exploit the organisms behaviors to keep themselves balanced. The animal is show

3、ing motivated behavior Negative Feedback systems are the primary homeostatic mechanisms . If a desired value, the If a desired value, the set pointset point, is deviated from, , is deviated from, compensatory action compensatory action begins.begins. . The The set zone set zone refers to refers to t

4、he range of tolerance in a the range of tolerance in a system.system. 1.1.Homeostasis Maintains Internal States Homeostasis Maintains Internal States within a Critical Rangewithin a Critical Range 2.2.Unavoidable Losses Require Us to Gain Unavoidable Losses Require Us to Gain Heat, Water, and FoodHe

5、at, Water, and Food Contents: u Temperature Regulation u Fluid Regulation u Food and Energy Regulation Temperature Regulation 一一 Body Temperature is a Critical Body Temperature is a Critical Condition for All Biological ProcessCondition for All Biological Process 二二 Some Animals Generate Heat; Some

6、Animals Generate Heat; Others Must Obtain Heat from the Others Must Obtain Heat from the EnvironmentEnvironment 三三 Which Behaviors Can Adjust Body Which Behaviors Can Adjust Body Temperature?Temperature? 四四 The Brain Monitors and Regulates The Brain Monitors and Regulates Body TemperatureBody Temper

7、ature 一. Body Temperature is a Critical Condition for All Biological Process 1.1.AsAs thethe interiorinterior ofof a a cellcell cools,cools, chemicalchemical reactionsreactions slowslow down, and some stop down, and some stop altogetheraltogether bilipid bilipid ( (双脂肪双脂肪) ) layerslayers thatthat ma

8、kemake upup cellularcellular membranesmembranes becomebecome soso disrupteddisrupted byby thethe formationformation ofof iceice moleculesmolecules thatthat cannotcannot re-formre-form eveneven whenwhen thawed.thawed. somesome animalsanimals thatthat cannotcannot avoidavoid subfreezingsubfreezing T T

9、 produceproduce “ “antifreezeantifreeze” ” consistingconsisting ofof specialspecial proteinprotein moleculesmolecules thatthat disruptdisrupt thethe formationformation ofof iceice crystalscrystals andand preventprevent damagedamage toto membranes.membranes. 一一. Body Temperature is a Critical Conditi

10、on for All Biological Process 1.1.AsAs thethe interiorinterior ofof a a cellcell cools,cools, chemicalchemical reactionsreactions showshow down,down, andand somesome stopstop altogether.altogether. 2.2.AtAt highhigh T,T, proteinprotein moleculesmolecules foldfold togethertogether improperlyimproperl

11、y andand thusthus dodo notnot functionfunction asas theythey should.should. thethe aminoamino acidsacids beginbegin toto breakbreak apartapart andand fusefuse togethertogether moremore oror lessless random,random, soso cancan saysay thethe tissuetissue is is fixedfixed ( (cookedcooked) ) brainbrain

12、cellscells areare especiallyespecially sensitivesensitive toto highhigh T.T. Temperature Regulation 一一 Body Temperature is a Critical Body Temperature is a Critical Condition for All Biological ProcessCondition for All Biological Process 二二 Some Animals Generate Heat; Some Animals Generate Heat; Oth

13、ers Must Obtain Heat from the Others Must Obtain Heat from the EnvironmentEnvironment 三三 Which Behaviors Can Adjust Body Which Behaviors Can Adjust Body Temperature?Temperature? 四四 The Brain Monitors and Regulates The Brain Monitors and Regulates Body TemperatureBody Temperature 二. Some Animals Gene

14、rate Heat; Others Must Obtain Heat from the Environment Cold-bloodedCold-blooded Others Must Obtain Heat from the Environment 1.1.EndothermsEndotherms Others Must Obtain Heat from the Environment 1.1.EndothermsEndotherms Others Must Obtain Heat from the Environment 1.1.EndothermsEndotherms Others Mu

15、st Obtain Heat from the Environment 1.1.EndothermsEndotherms Others Must Obtain Heat from the Environment 1.1.EndothermsEndotherms colder region; In animalIn animal, , body appendages body appendages such as such as the ears are smaller in arctic species than in related the ears are smaller in arcti

16、c species than in related tropical species.tropical species. 5. Body size and shape affect heat production and heat loss In human, taller, more slender body forms have evolved in the Tropics, and shorter, stockier physiques are more typical of colder region; Foxes Tropical Temperate Arctic 5. Body s

17、ize and shape affect heat production and heat loss Heat is exchanged with the environment primarily at Heat is exchanged with the environment primarily at the surface of the body.the surface of the body. Shape also affects the conservation of heat and Shape also affects the conservation of heat and

18、therefore energy. therefore energy. Fur of mammals and feathers of birds are special Fur of mammals and feathers of birds are special adaptations of the skin that insulate the body from adaptations of the skin that insulate the body from the environment .the environment . spend a great deal of time

19、grooming, and preeningspend a great deal of time grooming, and preening 二. Some Animals Generate Heat; Others Must Obtain Heat from the Environment 1.1.EndothermsEndotherms Some Animals Generate Heat; Others Must Obtain Heat from the Others Must Obtain Heat from the EnvironmentEnvironment 三三 Which B

20、ehaviors Can Adjust Body Which Behaviors Can Adjust Body Temperature?Temperature? 四四 The Brain Monitors and Regulates The Brain Monitors and Regulates Body TemperatureBody Temperature 三. Which Behaviors Can Adjust Body Temperature? 1.1.ChangingChanging exposureexposure ofof thethe bodybody surfacesu

21、rface e.g.e.g. byby huddlinghuddling oror extendingextending limbslimbs An iguana will lie on a warm rock to raise its temperature. It lies broadside to the sun until its temperature reaches 37, then turns to face the sun to absorb less heat. 三. Which Behaviors Can Adjust Body Temperature? 1.1.Chang

22、ingChanging exposureexposure ofof thethe bodybody surfacesurface 2.2.ChangingChanging externalexternal insulationinsulatione.g.e.g. byby usingusing clothingclothing oror nest.nest. 3.3.SelectingSelecting a a surroundingsurrounding thatthat is is lessless thermallythermally stressfulstressfule.g.e.g.

23、 byby movingmoving toto thethe shadeshade oror intointo a a burrowburrow 4.4.YoungYoung birdsbirds andand mammalsmammals needneed helphelp toto regulateregulate bodybody temperaturetemperature Physiological Physiological Physiological Thermoregulation: Newborn rats use brown-fat deposits to generate

24、 heat 三. Which Behaviors Can Adjust Body Temperature? 1.1.ChangingChanging exposureexposure ofof thethe bodybody surfacesurface 2.2.ChangingChanging externalexternal insulationinsulation 3.3.SelectingSelecting a a surroundingsurrounding thatthat is is lessless thermallythermally stressfulstressful 4

25、.4.YoungYoung birdsbirds andand mammalsmammals needneed helphelp toto regulateregulate bodybody temperaturetemperature Physiological Physiological social thermoregulationsocial thermoregulation Social Thermoregulation: huddle together Anesthetized pup remains in the core and becomes overheated Anest

26、hetized pup is pushed to periphery and becomes too cool. 三. Which Behaviors Can Adjust Body Temperature? 1.1.ChangingChanging exposureexposure ofof thethe bodybody surfacesurface 2.2.ChangingChanging externalexternal insulationinsulation 3.3.SelectingSelecting a a surroundingsurrounding thatthat is

27、is lessless thermallythermally stressfulstressful 4.4.YoungYoung birdsbirds andand mammalsmammals needneed helphelp toto regulateregulate bodybody temperaturetemperature 5.5.SomeSome endothermsendotherms survivesurvive byby lettingletting theirtheir bodybody T T plummetplummettorportorpor ( (蛰伏蛰伏) )

28、 Temperature Regulation 一一 Body Temperature is a Critical Body Temperature is a Critical Condition for All Biological ProcessCondition for All Biological Process 二二 Some Animals Generate Heat; Some Animals Generate Heat; Others Must Obtain Heat from the Others Must Obtain Heat from the EnvironmentEn

29、vironment 三三 Which Behaviors Can Adjust Body Which Behaviors Can Adjust Body Temperature?Temperature? 四四 The Brain Monitors and Regulates The Brain Monitors and Regulates Body TemperatureBody Temperature 四. The Brain Monitors and Regulates Body Temperature 1.1.ExperimentsExperiments anterioranterior

30、 hypothalamushypothalamus , , preopticpreoptic area(POA)area(POA) 2.2.LesionLesion experimentsexperiments regulationregulation byby locomotorlocomotor andand otherother behaviorsbehaviors commoncommon toto bothboth endothermsendotherms andand ectotherms;ectotherms; Lesions in the Lesions in the late

31、ral hypothalamus (LH) lateral hypothalamus (LH) abolish abolish behavioral regulationbehavioral regulation（行为调节）（行为调节）, but do not , but do not affect physiological responses such as shiveringaffect physiological responses such as shivering 四四. The Brain Monitors and Regulates Body Temperature 1.1.E

32、xperimentsExperiments anterioranterior hypothalamushypothalamus , , preopticpreoptic area(POA)area(POA) 2.2.LesionLesion experimentsexperiments regulationregulation byby locomotorlocomotor andand otherother behaviorsbehaviors commoncommon toto bothboth endothermsendotherms andand ectothermsectotherm

33、s; ; physiologicalphysiological regulationregulation characteristiccharacteristic ofof endothermsendotherms Physiological responses are impaired by lesions Physiological responses are impaired by lesions to the to the preopticpreoptic area (POA), area (POA), without disruption of without disruption

34、of behavior.behavior. 四四. The Brain Monitors and Regulates Body Temperature 1.1.ExperimentsExperiments anterioranterior hypothalamushypothalamus , , preopticpreoptic area(POA)area(POA) 2.2.LesionLesion experimentsexperiments 3.3.ReceptorsReceptors atat thethe surfacesurface ofof bodybody alsoalso mo

35、nitormonitor temperaturetemperatureshiver/sweat 4.4.DoseDose thethe bodybody havehave a a singlesingle mastermaster thermostat thermostat ( (温度调节装置温度调节装置) )? ? 4. Dose the body have a single master thermostat ? 1.A hierarchy of thermoregulatory circuits Spinal level Midbrain Hypothalamus (including

36、the POA) Thermoneutral （热平衡的）zones of thermoregulatory systems are narrower at higher levels of the nervous system than at lower levels The Basic thermoregulatory system: Afferents Skin surface Body core hypothalamus Neural regions Spinal cord Brainstem hypothalamus Effectors Behavioral responses Sh

37、ivering Heat seeking/avoiding Behaviors Autonomic responses Vasoconstriction/dilation Sweating Respiration Brown-fat stimulation Thyroid hormone secretion Contents: u Temperature Regulation u Fluid Regulation u Food and Energy Regulation Fluid Regulation 一一OurOur CellsCells EvolvedEvolved toto Funct

38、ionFunction in in SeawaterSeawater 二二TwoTwo InternalInternal CuesCues TriggerTrigger ThirstThirst 三三HomeostaticHomeostatic RegulationRegulation ofof SaltSalt is is RequiredRequired forfor EffectiveEffective RegulationRegulation ofof WaterWater 一一. Our Cells Evolved to Function in Seawater 1.1.TheThe

39、 firstfirst livingliving creaturescreatures onon EarthEarth arosearose in in thethe sea.sea. LandLand animalsanimals hadhad toto preventprevent dehydrationdehydration soso thatthat theirtheir cellscells wouldwould workwork perly. TheyThey neededneeded a a moremore oror lessless watertigh

40、twatertight outerouter layerlayer ofof cells,cells, andand theythey hadhad toto maintainmaintain thethe properproper concentrationconcentration ofof saltssalts andand otherother moleculesmolecules in in bodybody fluidsfluids 一一. Our Cells Evolved to Function in Seawater 1.1.TheThe firstfirst livingl

41、iving creaturescreatures onon EarthEarth arosearose in in thethe sea.sea. 2.2.WeWe mustmust relinquishingrelinquishing andand replacingreplacing thethe bodysbodys water,water, soso mustmust monitormonitor andand regulateregulate thethe compositioncomposition ofof bodybody fluidfluid Average Daily Wa

42、ter Balance of an Adult Human SourceQuantity (liters) Approximate intake Fluid water1.2 Water content of food1.0 Water from oxidation of food0.3 Total2.5 Approximate output Urine1.4 Evaporative lose0.9 Feces0.2 Total2.5 一一. Our Cells Evolved to Function in Seawater 1.1.TheThe firstfirst livingliving

43、 creaturescreatures onon EarthEarth arosearose in in thethe sea.sea. 2.2.WeWe mustmust relinquishingrelinquishing andand replacingreplacing thethe bodysbodys water,water, soso mustmust monitormonitor andand regulateregulate thethe compositioncomposition ofof bodybody fluidfluid 3.3.WaterWater in in

44、thethe humanhuman bodybody movesmoves backback andand forthforth betweenbetween twotwo majormajor compartmentscompartments 3. Water in the human body moves back and forth between two major compartments IntracellularIntracellular in this way animals ensure against dehydration. Fluid Regulation 一一OurO

45、ur CellsCells EvolvedEvolved toto FunctionFunction in in SeawaterSeawater 二二TwoTwo InternalInternal CuesCues TriggerTrigger ThirstThirst 三三HomeostaticHomeostatic RegulationRegulation ofof SaltSalt is is RequiredRequired forfor EffectiveEffective RegulationRegulation ofof WaterWater 三. Homeostatic Re

46、gulation of Salt is Required for Effective Regulation of Water 1.1.WeWe cannotcannot maintainmaintain waterwater in in thethe extracellularextracellular compartmentcompartment withoutwithout solutes.solutes. 2.2.TheThe numbernumber ofof NaNa+ + ionsions wewe possesspossess primarilyprimarily determi

47、nesdetermines howhow muchmuch waterwater wewe cancan retain.retain. 3.3.MineralocorticoidMineralocorticoid (盐皮质激素盐皮质激素), , inducesinduces thethe kidneyskidneys toto conserveconserve NaNa+ + Contents: u Temperature Regulation u Fluid Regulation u Food and Energy Regulation “We are dependent on food f

48、or “We are dependent on food for energyenergy and for and for building building and maintaining our bodies that and maintaining our bodies that hunger is a hunger is a compelling motive compelling motive and flavors and flavors are are powerful reinforcementspowerful reinforcements” ” “The need to e

49、at shapes our daily schedules “The need to eat shapes our daily schedules and molds our activities”and molds our activities” “Our basic reliance on food for energy and “Our basic reliance on food for energy and nutrition is shared with all other animals.”nutrition is shared with all other animals.”

50、Contents: 一一 Nutrient Regulation Requires the Anticipation of Future Needs 二二 Insulin is Crucial for the Regulation of Body Metabolism 三三 Experience Protects Us from Toxins in Food 四四Is There a Single Satiety or Hunger Center in the Brain 五五 Anorexia Nervosa and Bulimia Are Life-Threatening Eating D

51、isorders 一. Nutrient Regulation Requires the Anticipation of Future Needs 1. Food regulation is complicated 2. Most of Our Food Is Used to Provide Us with Energy 3. Carbohydrates Provide Energy for Body and Brain 1. Food regulation is complicated First reason for the greater complexity is that food

52、is needed not only to supply energy but also to supply nutrients. Nutrients Nutrients are chemicals that are not used as sources of energy but are required for the effective functioning of the body (for growth, maintenance, repair of body structures). We do not know all the nutritional requirement o

53、f the body. Amino acids: of the 20 amino acids found in our bodies, 9 are difficult or impossible for us to manufacture( essential amino acids) Vitamins: 15 Minerals: several 1. Food regulation is complicated First reason for the greater complexity is that food is needed not only to supply energy bu

54、t also to supply nutrients. Second reason is that no animal can afford to run out of energy or nutrients; there must be a reserve on hand at all times. Reserve I. Reserve V.S Mobility II. How the organism anticipates the need for energy and nutrients III. How the resources are moved in and out of va

55、rious body reservoirs. digestion 一一. Nutrient Regulation Requires the Anticipation of Future Needs 1. Food regulation is complicated 2. Most of Our Food Is Used to Provide Us with Energy 3. Carbohydrates Provide Energy for Body and Brain 2. Most of Our Food Is Used to Provide Us with Energy All the

56、energy we need to move, think, breath, and maintain body temperature is derived in the same way: it is released as the chemical bonds of complex molecules are broken to form smaller, simpler compounds. assess the amount of energy used in terms of calories. the calories of food are describing the pot

57、ential energy available. metabolic rate (kilocalories per day, kcal/day) about 75% of the ingested energy became available for use in body functions. 2. Most of Our Food Is Used to Provide Us with Energy All the energy we need to move, think, breath, and maintain body temperature is derived in the s

58、ame way: The available energy is used in one of three activities Processing of newly ingested food (8%) Basal metabolism (55%) Active behavioral processes (1213%) 2. Most of Our Food Is Used to Provide Us with Energy All the energy we need to move, think, breath, and maintain body temperature is der

59、ived in the same way: The available energy is used in one of three activities The rate of basal metabolism The rate of basal metabolism p Max Kleiber (1947) this rule has been shown to apply from the largest mammals to mice. kcal/day=70weight0.75 The relation between body size and metabolism The rat

60、e of basal metabolism p Max Kleiber (1947) this rule has been shown to apply from the largest mammals to mice. it holds across species but not within speciesbody weight is only one factor affecting metabolic rate a) within a species, an animals basal metabolic rate may depart significantly from the