Human Physiology

I. Nervous System.- 1 Function of Nerve Cells.- 1.1 Nerve Cells: General Structure and Function.- 1.2 The Resting Potential.- Measurement of the Membrane Potential.- Charge Distribution at the Membrane.- K + Distribution and Resting Potential.- Contribution of CI- to the Resting Potential.- The Passive Na+ Inflow.- The Sodium Pump.- Survey of the Ion Currents through the Membrane.- 1.3 The Action Potential.- Time Courses of Action Potentials.- The Origin of the Action Potential.- Kinetics of Ionic Currents during Excitation.- The Inactivation of the Na + System.- Ion Currents during the Afterpotentials.- 1.4 Extracellular Space and Neuroglia.- 1.5 Electrotonus and Stimulus.- Electrotonus in the Case of Homogeneous Current Distribution.- Electrotonus in Elongated Cells.- Stimulus and Threshold.- Threshold Shifts; Accommodation.- 1.6 Propagation of the Action Potential.- Measurement of Conduction Velocity.- Mechanisms of Conduction.- 1.7 The Generation of Excitation in Receptors.- The Receptor Potential.- Transformation of the Receptor Potential into Excitation.- Adaptation.- Coding of Stimulus Amplitude as Impulse Frequency.- 1.8 Axonal Transport.- Rapid Axonal Transport.- Retrograde Transport.- Mechanism of Transport.- Axonal Transport and Pathological Conditions.- 1.9 References.- 2 Muscle.- 2.1 The Molecular Mechanism of Contraction.- Sliding-Filament Theory.- The Chemomechanical Energy Transformations.- 2.2 The Regulation of Muscle Contraction.- Excitation-Contraction Coupling.- Regulation of Muscle Force in the Human Body.- 2.3 Muscle Mechanics.- Isometric Contractile Force and Muscle Length.- Relation between Load and Shortening of the Muscle.- Relation between Contraction Velocity and Force (Load).- 2.4 Muscle Energetics.- 2.5 Smooth Muscle.- 2.6 References.- 3 The Transmission of Excitation from Cell to Cell.- 3.1 The Neuromuscular Junction: A Chemical Synapse.- Structural Elements of the End Plate.- The End-Plate Potential.- The Release of Transmitter Substance.- The Transmitter Acetylcholine; Its Subsynaptic Receptors.- Neuromuscular Blockade.- 3.2 Central Excitatory Chemical Synapses.- The Excitation of the Motoneuron.- EPSPs in Other Nerve Cells.- 3.3 Central Inhibitory Chemical Synapses.- Postsynaptic Inhibition.- Presynaptic Inhibition.- 3.4 The Transmitters at Chemical Synapses.- Absence of Transmitter Specificity.- Acetylcholine as a Transmitter Substance in the Nervous System.- Adrenergic Transmitter Substances.- Amino Acids.- Other Possible Transmitters.- 3.5 Electrical Synapses.- 3.6 References.- 4 Physiology of Small Groups of Neurons; Reflexes.- 4.1 Typical Neuronal Circuits.- Divergence and Convergence.- Temporal and Spatial Facilitation; Occlusion.- Simple Inhibitory Circuits.- Activity-Enhancing Circuits and Mechanisms.- Synaptic Depression.- 4.2 Reflexes.- Components of a Reflex Arc; Reflex Time.- The Monosynaptic Reflex Arc.- Polysynaptic Reflexes.- 4.3 References.- 5 Motor Systems.- 5.1 Survey of the Neural Control of Posture and Movement.- 5.2 Spinal Motor Systems.- Receptors for the Spinal Sensory and Motor Systems.- Functions of the Muscle Spindles and Tendon Organs.- Polysynaptic Motor Reflexes.- Functions That Persist in the Isolated Spinal Cord.- 5.3 Motor Functions of the Brainstem.- Functional Anatomy of the Brainstem Motor Centers.- Motor Function in Decerebrate Animals.- Motor Functions of the Midbrain Animal.- 5.4 The Cerebellum.- Functional Anatomy of the Cerebellum.- The Cerebellar Cortex.- Afferent and Efferent Connections of the Cerebellum.- Functions of the Cerebellum.- Pathophysiological Aspects.- 5.5 Functions of the Motor Cortex and the Basal Ganglia.- Which Are the Motor Areas of the Cortex?.- Functional Organization of the Motor Cortex.- Efferent Connections of the Motor Cortex.- The Basal Ganglia.- Motor Cortex, Thalamus, Basal Ganglia and Movement.- The Drive to Act and the Movement Design.- 5.6 Pathophysiology of Motor Systems.- Peripheral Paralysis.- Pathophysiology ofthe Basal Ganglia.- Pathophysiology of the Motor Cortex and its Efferents.- 5.7 References.- 6 The Autonomic Nervous System.- 6.1 The Peripheral Autonomic Nervous System.- Anatomical Subdivisions.- The Actions of Sympathetic and Parasympathetic Fibers on Effector Organs.- Neurohumoral Transmission in the Peripheral Autonomic Nervous System.- The Adrenal Medulla. The Systemic Actions of Adrenalin and Noradrenalin.- Synaptic Organization of the Peripheral Autonomic Nervous System.- 6.2 Central Organization of the Autonomic Nervous System in Spinal Cord and Brainstem.- Resting Activity in the Autonomic Nervous System.- Autonomic Reflexes of the Spinal Cord.- Autonomic Capabilities of the Brainstem.- 6.3 Micturition and Defecation.- Neuronal Control of Bladder Evacuation.- Neuronal Control of Bowel Evacuation.- 6.4 Genital Reflexes.- Genital Reflexes in the Man.- Genital Reflexes in the Woman.- Extragenital Reactions during the Sexual Response Cycle.- 6.5 Functions of the Hypothalamus.- Functional Anatomy of the Hypothalamus.- The Hypothalamo-Hypophyseal System.- Hypothalamus and Cardiovascular System.- Hypothalamus and Behavior.- 6.6 Limbic System and Behavior.- Elements of the Limbic System.- Functions of the Limbic System.- Emotions and the Limbic System.- Monoaminergic Systems and Behavior.- 6.7 References.- 7 Integrative Functions of the Nervous System.- 7.1 General Physiology of the Cerebral Cortex.- Functional Histology of the Cerebral Cortex.- Electrophysiological Correlates of Cortical Activity.- The Electroencephalogram (EEG).- Cerebral Activity, Metabolism and Blood Flow.- 7.2 Waking and Sleeping.- Circadian Periodicity as the Basis of the Waking/Sleeping Rhythm.- Phenomenology of Waking and Sleeping.- Mechanisms of Waking and Sleeping.- 7.3 Neurophysiological Correlates of Consciousness and Speech.- Consciousness in Humans and Animals.- Functional and Structural Prerequisites for Consciousness.- Neurophysiological Aspects of Speech.- 7.4 Learning and Memory.- Human Memory.- Disturbances of Memory.- Neuronal Mechanisms.- Biochemical (Molecular) Mechanisms of the Engram.- Learning in the Autonomic Nervous System.- 7.5 The Frontal Lobes.- Inferences from Frontal-Lobe Lesions in Humans.- Frontal-Lobe Symptoms in Animal Experiments.- 7.6 References.- II. Sense Organs.- 8 General Sensory Physiology.- 8.1 Basic Concepts.- Objective and Subjective Sensory Physiology.- Basic Dimensions of Sensation.- 8.2 General Objective Sensory Physiology.- Specificity of Sense Organs.- Neuronal Connectivity in the Sensory System.- Receptive Field.- Intensity/Response Relationships.- 8.3 Stimulus and Behavior.- Conditioned Reflex and the Conditiorung Process.- Measurement of Dark Adaptation by Operant Conditioning.- 8.4 General Subjective Sensory Physiology.- Measurement of the Intensity of a Sensation or Perception.- Simultaneous Changes in Dimension.- Spatial Dimension of Sensation; Contrast.- Time Dimension of Sensation; Adaptation.- Affective and Intentional Aspects of Perception.- 8.5 References.- 9 Somatovisceral Sensibility: Processing in the Central Nervous System.- 9.1 Survey of the Central Structures for the Processing of Somatosensory Information.- The Specific and Nonspecific Afferent Somatosensory Systems.- 9.2 Connections of Afferents in the Spinal Cord.- Neurophysiology of the Dorsal Hom.- Ascending Pathways in the Spinal Cord.- 9.3 Somatosensory Functions of the Brainstem.- The Trigeminal Nerve and Its Connections.- The Reticular Formation.- 9.4 The Thalamus.- Anatomical and Functional Survey.- The Specific Thalamic Nucleus of the Somatosensory System.- 9.5 Somatosensory Projections Areas in the Cortex.- Topographic Organization of the Somatosensory Cortex.- Neuronal Organization of the Somatosensory Cortex.- Cortex and Perception.- 9.6 Control of Afferent Input in the Somatosensory System.- 9.7 References.- 10 Somatovisceral Sensibility: Cutaneous Senses, Proprioception, Pain.- 10.1 Mechanoreception.- Subjectively Measurable Properties of Mechanoreception.- Cutaneous Mechanoreceptors.- Receptor Function and Mechanoreception.- 10.2 Proprioception.- Qualities of Proprioception.- Proprioceptors.- 10.3 Thermoreception.- Cutaneous Temperature Sensations.- Cold and Warm Points; Spatial Thresholds.- Cold and Warm Receptors.- Receptor Function and Thermoreception.- Special Forms of Thermo reception.- 10.4 Somatic and Visceral Pain.- Qualities of Pain.- Measurement of the Intensity of Pain; Adaption to Pain.- Neurophysiological Basis of Pain.- 10.5 Special and Abnormal Forms of Pain; Pain Therapy.- Special Forms of Pain.- Peripheral and Central Disturbances of Nociception.- Pain Therapy.- 10.6 Reference.- 11 Vision and Eye Movements.- 11.1 Light and Sight.- The Duplicity Theory of Vision.- Active Seeing.- 11.2 The Eye and its Dioptric Apparatus.- The Structure of the Eye.- Tears.- The Production of an Image on the Retina.- Regulatory Processes in the Dioptric Apparatus.- Optical Defects and Refractive Anomalies.- Measurement of Refractive Errors and Prescription of Corrective Lenses.- Examination of the Interior of the Eye with the Ophthalmoscope.- Intraocular Pressure.- 11.3 Signal Reception and Processing in the Retina.- The Transduction Process in Vision.- The Corneoretinal Potential and the Electroretinogram (ERG).- Receptive Fields of Retinal Ganglion Cells.- Neurophysiological Basis of Simultaneous Contrast.- Light/Dark Adaptation, Overstimulation, Afterimages.- The Temporal Properties of Transmission in the Retina.- 11.4 Signal Processing in the Central Visual System.- The Central Visual Pathway.- Signal Processing in the Superior Colliculi.- Signal Processing in the Lateral Geniculate Nucleus (LGN).- Signal Processing in the Visual Cortex.- Neurophysiological Bases of Shape Perception.- The Measurement of Visual Acuity.- Measurement of the Visual Field by Perimetry.- The Visual Evoked Potential (VEP).- 11.5 Binocular Vision.- 11.6 Color Vision.- Colors and the Measurement of Color.- Theories of Color Vision.- Disturbances of Color Vision.- 11.7 Eye Movements, Movement Perception and Sensorimotor Integration in Vision.- Measurement of Eye Movements.- The Binocular Coordination of Eye Movements.- The Temporal Properties of Eye Movements.- The Neuronal Control of Eye Movements.- Neurophysiology of the Control of Eye Movements and Gaze Direction.- The Perception of Movement.- Movement Perception and Motion of the Observer.- Eye Movements and Movement Perception.- 11.8 References.- 12 Physiology of the Sense of Equilibrium, Hearing and Speech.- 12.1 Physiology of the Sense of Equilibrium.- Physiology of the Peripheral Sensory Apparatus.- The Central Vestibular System.- The Vestibular Reflexes; Clinical Tests.- 12.2 Physiology of Hearing.- The Physical Properties of the Sound Stimulus (Acoustics).- Anatomical Bases of the Process of Hearing; the Peripheral Ear.- Psychophysics of Auditory Sensations.- The Role of the Middle Ear.- Auditory Processes in the Inner Ear.- The Central Auditory System.- Pathophysiology of Auditory Defects..- 12.3 Physiology of the Speech Apparatus.- Basic Properties of the Acoustic Signal Produced in Speaking.- Phonation.- Articulation.- Sound Spectrography.- Speech Impediments.- 12.4 References.- 13 Taste and Smell.- 13.1 Characterization of the Chemical Senses.- 13.2 The Sense of Taste.- Receptors and Neurons.- Gustatory Ability in Man.- 13.3 The Sense of Smell.- Receptors.- Odor Qualities.- Sensitivity, Coding.- Central Processing.- 13.4 References.- 14 Thirst and Hunger: General Sensations.- 14.1 Thirst.- The Origin of Thirst.- Receptors and Central Mechanisms.- The Quenching of Thirst.- Clinical Thirst.- 14.2 Hunger.- Origin of the Sensation of Hunger.- Satiety.- Psychological Factors in Hunger; Appetite.- Central Mechanisms of Hunger and Satiety.- 14.3 References.- 15 Cybernetic Aspects of the Nervous System and Sense Organs.- 15.1 The Sensory System in Terms ofInformation Theory.- The Concept ofInformation Theory.- The Ideal Receptor: Coding and Information Content.- The Technological Unit of Information.- Information Transmission in an Ideal Receptor.- Information Transmission in a Real Receptor.- Redundancy.- Neurophysiology and Psychophysics.- 15.2 The Spinal Motor System Interpreted as a Control Circuit.- The Terminology of Control Theory.- The Stretch Reflex as a Control System.- Change in Gain of the Length Controller.- Dynamic Properties of Control Systems.- Operation of a Servomechanism.- Concatenation of Segmental and Supraspinal Control Circuits.- 15.3 References.- III. Blood, Circulation and Respiration.- 16 Functions of the Blood.- 16.1 Basic Concepts.- Functions of the Blood.- Blood Volume.- Hematocrit.- 16.2 Blood Plasma.- Plasma Electrolytes.- Plasma Proteins.- Transported Plasma Components.- 16.3 Erythrocytes.- Number, Shape and Size.- Production, Life Span and Destruction.- Metabolism and Membrane Properties.- Special Physicochemical Properties.- 16.4 Leukocytes.- Properties Common to All Leukocytes.- Granulocytes.- Lymphocytes.- Monocytes.- 16.5 Thrombocytes.- 16.6 Hemostasis and Coagulation.- Basic Considerations.- Clotting Factors and the Process of Coagulation.- Fibrinolysis.- Disturbance and Inhibition of Coagulation, Tests of Clotting Activity.- 16.7 The Role of the Blood in Defense.- Basic Considerations.- Specific Defense Mechanisms.- Unspecific Defense.- 16.8 Human Blood Groups.- AB0 System.- Rh System.- Blood Transfusion.- 16.9 References.- 17 Function of the Heart.- 17.1 Structure and General Functional Aspects.- 17.2 Basic Processes of Excitation and Excitation-Contraction Coupling.- Origin and Spread of Excitation.- Characteristics of the Elementary Process of Excitation.- Relationships between Excitation and Contraction: Excitation-Contraction Coupling.- Autonomic Innervation; the Basic Actions of Autonomic Transmitters.- 17.3 Electrocardiogram.- Origin of the ECG.- Electrode Arrangements.- Limb Leads.- Chest Leads.- Use of the ECG in Diagnosis.- Examples of ECG Abnormality.- 17.4 The Mechanical Action of the Heart.- Action of the Heart Valves.- Sequence of Valve Action.- Functional Anatomy and Pattern of Ventricular Movement.- External Signals of Heart Activity.- Invasive Techniques: Intracardial Measurement.- 17.5 Dynamics of Adjustment to Changing Work Loads.- Pressure-Volume Relations in the Isolated Heart.- Autoregulatory Responses to Acute Volume and Pressure Loads.- Dynamics of the Innervated Heart in situ.- Adaptation ofthe Heart to Prolonged Exertion.- 17.6 Energetics of the Heartbeat.- Cardiac Work and Power.- Oxygen and Nutrient Consumption.- The Myocardial Blood Supply.- Cardiac Insufficiency.- 17.7 References.- 18 Functions of the Vascular System.- 18.1 Fundamentals of Hemodynamics.- The Physics of Blood Flow.- Types of Flow.- Relations between Volume Flow and Resistance to Flow.- 18.2 Properties of the Vessel Walls.- Structure of the Walls.- Transmural Pressure, Vessel Diameter and Wall Tension.- Pressure-Volume Relationships.- Pressure-Volume Flow Relationships in Vessels of Different Types.- 18.3 Functional Organization of the Vascular System.- The Functional Categories of Vessels.- Resistances in the Vascular System.- Blood Volume in the Vascular System.- 18.4 The Arterial Part of the Systemic Circulation.- Flow in the Arterial System.- Pressures in the Arterial System.- Effects of the Elasticity of Vessels.- Analysis of Pulse Contour.- 18.5 Venous Part of the Systemic Circulation.- Pressures and Flow in the Venous System.- Central Venous Pressure and Venous Return.- Effect of Gravity on the Pressures in the Vascular System.- Mechanisms to Increase Venous Return.- 18.6 Microcirculation.- The Terminal Vascular Bed.- Capillary Exchanges.- 18.7 The Lymphatic System.- 18.8 Regulation of Regional (Local)Blood Flow.- Basic Features of Regional Regulation.- Local Regulating Mechanisms.- Neural Regulation.- Chemical and Hormonal Effects.- 18.9 Regulation of the Overall Circulation.- Basic Features of General Circulatory Regulation.- Short-Term Control Mechanisms.- Baroreceptor Reflexes.- Cardiac Stretch-Receptor Reflexes.- Reflexes Involving Arterial Chemoreceptors.- Ischemic Response of the CNS.- Effects of Adrenalin and Noradrenalin on the Circulatory System.- Intermediate-Term Control Mechanisms.- Long-Term Control Mechanisms.- Central Control of the Circulation.- 18.10 The Pulmonary Circulation.- Hemodynamics of the Pulmonary Circulation.- Special Functional Features.- Regulatory Mechanisms in the Pulmonary Circuit.- 18.11 Circulatory Adjustments to Physiological and Pathological Circumstances.- Human Blood Pressure.- Rhythmic Fluctuations in Blood Pressure.- Effects of Posture.- Exercise.- Thermal Stress.- Loss of Blood.- Cardiovascular Shock.- 18.12 Circulation through Special Organs and its Control.- Coronary Circulation.- Cerebral Circulation.- Hepatic and Portal Circulation.- Renal Circulation.- Circulation in Skeletal Muscle.- Cutaneous Circulation.- Uterine and Fetal Circulations.- 18.13 Measurement of Pressure, Flow and Volume in the Vascular System.- Pressure Measurement.- Measurement of Flow.- Measurement of Blood Volume.- 18.14 References.- 19 Pulmonary Respiration.- 19.1 Breathing Movements.- Respiratory Excursions of the Thorax.- Function of the Respiratory Muscles.- Transmission of Thorax Motion to the Lung.- 19.2 Ventilation.- LI:lflg Volumes and Capacities.- Measurement of Lung Volumes and Volumes Respired.- Anatomical and Functional Dead Space.- Alveolar Ventilation.- Artificial Respiration.- 19.3 Mechanical Factors in Breathing.- Elasticity of Lung and Thorax.- Nonelastic Resistances.- Pressure-Volume Relations in the Breathing Cycle.- Tests of Respiratory Mechanics.- 19.4 Exchange of Gases.- Alveolar Gas Concentrations.- Alveolar Partial Pressures.- Diffusion of Respiratory Gases.- Net Gas Exchange in Normal and Pathological Conditions.- 19.5 The Control of Respiration.- Respiratory Centers.- Mechanical Control of Respiration.- Chemical Control of Respiration.- Other Respiratory Drives.- 19.6 References.- 20 Blood Gas Transport and Acid-Base Balance.- 20.1 The Structure and Properties of Hemoglobin.- Structure of the Hemoglobin Molecule.- Light Absorption by Hemoglobin.- Hemoglobin Concentration in Blood; Mean Corpuscular Hemoglobin.- 20.2 The O2-Transport Function of the Blood.- Physical Solubility of Gases.- The Binding of Oxygen to Hemoglobin.- Factors Mfecting the O2 Dissociation Curve.- Hemoglobin-Carbon Monoxide Binding.- 20.3 The CO2-Transport Function of the Blood.- Forms of CO2 Transport.- CO2 Dissociation Curves.- 20.4 The Acid-Base Status of the Blood.- The Blood pH.- The Buffer Properties of the Blood.- pH-Regulating Mechanisms.- 20.5 References.- 21 Tissue Respiration.- 21.1 Metabolism and Oxygen Requirements of the Tissues.- Cellular Metabolism and Energy Conversion.- Biological Oxidation in the Mitochondria.- Tissue Oxygen Requirements.- 21.2 Tissue Oxygen Supply.- Tissue Oxygen Reserves.- O2 Availability and Utilization.- Respiratory Gas Exchange in the Tissues.- O2 Partial Pressures in the Tissues.- 21.3 Regulation of O2 Supply and Effects of O2 Deficiency.- Mechanisms for Matching Supply to Demand.- The Causes oflnadequate O2 Supply.- O2 Therapy; O2 Poisoning.- Reversible and Irreversible Disturbance in Acute Tissue Anoxia.- 21.4 References.- IV. Metabolism, Digestion and Excretion. Endocrine Regulation.- 22 Energy Balance.- 22.1 Energy Expenditure.- 22.2 Parameters of Metabolism.- Metabolic Parameters of Cells.- Metabolic Parameters of the Whole Organism.- 22.3 Measurement Techniques.- Direct Measurement of Metabolic Rate.- Indirect Measurement of Metabolic Rate.- Measurement of the Metabolic Rate of Single Organs.- 22.4 Measurement of the Oxygen Uptake of the Whole Body.- Closed Systems.- Open Systems.- 22.5 Diagnostic Significance of Energy Expenditure.- 22.6 References.- 23 Heat Balance and the Regulation of Body Temperature.- 23.1 Heat Production, Body Temperature and Body Size.- 23.2 The Temperature of the Human Body.- Local Temperature Differences (Temperature Gradients).- Periodic Fluctuations in Core Temperature.- Body Temperature during Exercise.- 23.3 Heat Loss.- Internal Heat Flow.- External Heat Flow.- Environmental Factors and Thermal Comfort...- 23.4 The Regulation of Body Temperature.- Effector Outputs in Thermoregulation.- Thermoreception.- Integrative Processes and Central Nervous Structures for Thermoregulation.- The Set Point and its Adjustment.- 23.5 Ontogenetic and Adaptive Changes in Thermoregulation.- Thermoregulation in the Newborn.- Long-Term Adaptation to the Environment.- 23.6 Pathophysiology of Thermoregulation.- Fever.- Failure of Thermoregulation at Extreme Temperatures.- 23.7 References.- 24 Work Physiology; Environmental Physiology.- 24.1 Fundamentals of Work Physiology.- Load, Performance and Strain.- Types of Performance.- Ergometry.- 24.2 Adjustments to Physical Loads.- Adjustments of the Dynamically Working Musculature.- Cardiovascular Parameters during Dynamic Work.- Oxygen Uptake and Respiration during Dynamic Work.- Blood Parameters during Dynamic Work.- Thermoregulation during Dynamic Work.- Hormonal Regulation during Dynamic Work.- Adjustments to Static Work.- 24.3 Responses of the Organism to Non-Physical Loads.- Responses to Psychological Loads.- 24.4 Limits of Performance Capacity.- Specific Performance Limits.- 24.5 Fatigue.- Fatigue and Recovery.- Physical Fatigue.- Psychological Fatigue.- Overloading and Exhaustion.- Feedback of Performance.- 24.6 Training and Adaption.- Special Forms of Training.- Degree of Adaptation.- Variability in Performance Capacity.- Shift Work.- Deficiency of Movement; Physical Therapy.- 24.7 Performance and Aptitude Tests.- Primary Test Criteria.- The Problem of the Norm.- Performance Tests.- Interpretation of Performance Tests.- 24.8 High-Altitude Physiology.- Oxygen Deficiency.- Short-Term Adjustment to High Altitude.- Acclimation to High Altitude.- Air and Space Travel.- 24.9 Diving.- Diving without Equipment.- Diving with Equipment.- Orientation under Water.- 24.10 References.- 25 Nutrition.- 25.1 Foods: Their Composition and Function.- Foodstuffs.- Vitamins.- Water, Salts, Trace Elements.- Condiments and Crude Fiber.- Residues.- 25.2 Nutritional Requirements; Symptoms of Deficiency and Overdosage.- Foodstuffs.- Vitamins.- Water, Salts, Trace Elements.- 25.3 Utilization of Foodstuffs; Dietetics.- Utilization.- Balanced Diet.- Special Diets.- 25.4 Evaluation of Body Weight and Body Surface Area.- Obesity as a Risk Factor.- Composition of the Body.- Surface Area of the Body.- 25.5 References.- 26 Functions of the Gastrointestinal Canal.- 26.1 Gastrointestinal Motility and Secretion.- Mouth and Esophagus.- Stomach.- Small Intestine.- Large Intestine and Rectum.- 26.2 Digestion and Absorption.- Digestion and Absorption of Protein.- Digestion and Absorption of Carbohydrates.- Digestion and Absorption of Fats.- Absorption of Vitamins, Water and Minerals.- 26.3 References.- 27 The Function of the Kidneys.- 27.1 Fundamentals of Renal Physiology.- Outline of Kidney Anatomy.- Features of Kidney Function.- Renal Excretion and the Clearance Concept.- 27.2 Renal Circulation.- Blood Flow through the Kidneys.- Oxygen Consumption and Metabolism of the Kidney.- 27.3 The Glomerular Filtration Process.- Morphological and Biophysical Fundamentals.- Glomerular Filtration Rate and Glomerular Filtrate.- 27.4 Tubular Transport Processes.- Tubular Reabsorption and Secretion of Organic Substances.- Tubular Reabsorption of Water and Electrolytes.- Hormonal Influences on Tubular Ion Transport and Water Reabsorption.- 27.5 The Concentrating of Urine in the Countercurrent System of the Renal Medulla.- 27.6 Regulatory Function of the Kidneys.- Regulation of the Osmotic Concentration of the Extracellular Fluid.- Regulation of the Extracellular Fluid Volume.- Regulation of Acid-Base Balance by the Kidneys.- 27.7 Renal Pathophysiology.- 27.8 References.- 28 Water Balance; Transport of Fluids and Solutes.- 28.1 Water Balance.- Body Water and Water Turnover.- Fluid Compartments in the Body.- 28.2 Biophysical Bases of the Transport of Fluids and Solutes in the Body.- Diffusion, Osmosis and Filtration.- Equilibrium Distribution of Ions.- Special Features of Transport through Biological Membranes.- 28.3 References.- 29 Functions of the Endocrine System.- 29.1 General Endocrinology.- Terminology.- Functional Significance and Mode of Action of Hormones.- Experimental Techniques.- 29.2 The Hypothalamic-Hypophyseal System.- Neurohypophysis and Functionally Associated Hypothalamic Nuclei.- Adenohypophysis and the Hypophysiotropic Zone of the Hypothalamus.- Hormones of the Adenohypophysis.- 29.3 The Endocrine Glands and Hormones Controlled by the Adenohypophysis.- The Adrenal Cortex and the Glucocorticoids.- The Thyroid Gland and the Hormones Thyroxin and Triiodothyronine.- The Gonads and the Sex Hormones.- 29.4 The Sympathico-Adrenal System.- Hormones of the System and Sites of Production.- Actions of Noradrenalin and Adrenalin.- Control of the Secretion of Noradrenalin and Adrenalin.- 29.5 Pancreatic Hormones and the Control of Blood Glucose.- Islet-Cell Hormones.- Regulation of Blood Glucose Concentration.- 29.6 The Hormonal Control of Mineral Balance.- Na + and K + Balance.- Calcium and Phosphate Balance.- 29.7 Gastrointestinal Hormones.- 29.8 Peripheral Topics in Endocrinology.- "Tissue Hormones".- Polypeptides and Amines; the APUD System.- Erythropoietin, Prostaglandins.- Organs with Uncertain or Unclear Endocrine Function.- 29.9 References.- 30 Appendix. Physiological Units.- 31 Subject Index.