Adaptation to Environment

1 Adaptations to Intertidal Life 1.1 The Nature of the Intertidal Environment 1.1.1 Simple Models of a Generalized Sea-Shore 1.1.2 Towards a More Complex Mode! 1.2 Strategies of Adaptation for Survival in the Intertidal Zone 1.2.1 The Evasion of Environmental Stress 1.2.2 Structural and Behavioral Maintenance of Heat Balance 1.2.3 Physiological Limits of Survival 1.3 Strategies in the Competition for Energy in the Intertidal Zone 1.3.1 Compensation in the Rate of Energy Input 1.3.2 Maintenance of Aerobic Respiration 1.3.3 Reduction in the Metabolic Expenditure of Energy 1.4 Conclusion 2 Settlement Responses in Marine Organisms 2.1 Introduction 2.2 Behavior Prior to Settlement 2.3 Settlement Behavior 2.3.1 The Cyprid of Balanus Balanoides 2.3.2 Behavior of Other Invertebrate Larvae 2.4 Prevention of Settlement 3 Biochemical Adaptations to Temperature 3.1 Introduction 3.2 The Basic Effects of Temperature on Marine Organisms 3.2.1 The Critical Element of Time 3.2.2 The Effects of Temperature on Biochemical Structures and Processes 3.3 Endothermy in the Marine Environment: Physiological and Anatomical Avenues of Escape from Thermal Stress 3.3.1 Basic Problems of Endothermy in an Aqueous Environment 3.3.2 Mechanisms of Heat Generation 3.3.3 Heat Retention Mechanisms 3.4 Ectothermy 3.4.1 Temperature Compensation of Metabolic Rates 3.4.2 The Roles of Multiple Enzyme Forms in Temperature Adaptation 3.4.3 Temperature-Membrane Interactions 3.4.4 Freezing Avoidance Mechanisms in Marine Teleosts 3.5 Concluding Comments 4 Primitive Respiratory Adaptations 4.1 Introduction 4.1.1 Preface 4.1.2 The Thesis 4.2 Ventilation 4.3 The Gill 4.4 The Circulatory Systems 4.4.1 Structural Design 4.4.2 Fluid Flow 4.4.3 PO2 and Ph 4.5 The Heart 4.6 The Red Cell 4.6.1 Colloid Osmotic Pressure 4.6.2 Viscosity 4.6.3 Haemoglobin Excretion 4.6.4 Biosynthetic Control 4.6.5 Intracellular Control Factors 4.7 Respiratory Pigments 4.7.1 Haemoproteins 4.7.2 Haemerythrins 4.7.3 Velocity of Ligand Combination 4.8 Summary 4.9 Glossary 5 Enzyme and Metabolic Adaptations to Low Oxygen 5.1 Introduction 5.2 Glycolytically-Based Strategies of Anoxia Adaptation 5.2.1 Biochemical Requirements and Solutions 5.2.2 Multiple Control Sites in Muscle Glycogenolysis 5.2.3 Strategic Positioning and Control Functions of Glycogen Phosphorylase 5.2.4 Autocatalytic Activation of Muscle Glycolysis Probably Depends on Phosphofructokinase 5.2.5 Maintenance of Redox Balance During Anaerobic Glycolysis in Muscle 5.2.6 Hallmarks That Make Muscle Glycolysis a 'Good Anaerobic Machine' 5.2.7 Muscle Glycolysis in Marine Mammals 5.2.8 Function of a High Muscle Fdpase Activity in Diving Mammals 5.2.9 The Regulatory Nature of Muscle Pyruvate Kinase in Diving Mammals 5.2.10 Metabolic Fuels in Muscle of Marine Mammals 5.2.11 How is Lipid 'Spared' During Anaerobic Glycogenolysis? 5.2.12 How is Glycogen 'Spared' During Aerobic Periods 5.2.13 Summary: Key Properties of Muscle Glycolysis in Diving Vertebrates 5.2.14 Anoxia Tolerance of Diving Turtles 5.2.15 The Anoxic Turtle Heart 5.3 Non-Glycolytic Mechanisms of Anoxia Adaptation 5.3.1 Storage Substrates and Anaerobic End Products 5.3.2 Anaerobic Metabolic Organisation in Bivalves 5.3.3 Energy Yield in Anoxic Oyster Muscle 5.3.4 Conflicting Metabolic Demands Imposed by Simultaneous Requirements for Anaerobiosis and Hyperosmotic Regulation 5.4 Non-Glycolytic Mechanisms of Anaerobiosis in Vertebrates 5.4.1 Introduction 5.4.2 Quantitative Significance 5.4.3 Role of Alanine and Aspartate Aminotransferases in Muscle Redox Balance 5.5 Concluding Comments and Generalization 6 Physiological Adaptation to Life in Estuaries 6.1 Introduction 6.2 Tolerance and Mechanisms of Regulation in Brackish Waters 6.2.1 Detection and Avoidance of Unfavorable Conditions 6.2.2 Tolerance of Extreme Conditions on a Short Term Basis 6.2.3 Physiological and Morphological Adaptation to Salinity Change 6.2.4 Physical and Chemical Factors Influencing Transport Rates 6.2.5 Affinity of the Ion Transport System 6.2.6 Racial Differences in Regulatory Capacity 6.2.7 Osmoregulatory Work 6.2.8 Calculations 6.3 Oxygen Uptake 6.4 Reproduction and Maintenance of Station within Estuaries 6.4.1 Salinity Tolerance of Young Stages 6.4.2 Factors Involved in the Maintenance of Larval Stages in Estuaries 6.5 Summary and Conclusions7 Rhythmic Behavior and Reproduction in Marine Animals 7.1 Introduction 7.2 Vertical Migration Rhythms in Plankton 7.3 Behavioral Rhythmicity and Position Maintenance in Estuaries 7.4 Rhythmic Activity in Benthic Animals 7.4.1 The Clock Mechanism 7.4.2 Environmental Synchronisation and Entrainment 7.5 Adaptive Significance of Behavioral Rhythms 7.6 Rhythmic Patterns of Reproduction 7.6.1 Adaptive Value 7.6.2 Physiological and Environmental Control 8 Vision in Pelagic Animals 8.1 Introduction 8.2 Light Underwater 8.3 Verticalzonation 8.4 Scotopic Vision 8.4.1 The Sensitivity Hypothesis 8.4.2 The Contrast Hypothesis 8.5 Photopic Vision in the Epipelagic Zone 8.6 The Eye of Fishes 8.6.1 Yellow Lens and Cornea 8.6.2 Tubular Eyes 8.6.3 Retinal Diverticula 8.6.4 The Deep-Sea Retina 8.7 Polarized Light 8.8 Body Camouflage—Silvery Sided Fishes 8.9 Bioluminescence 8.10 Summary 9 Biochemical Adaptations to Pressure 9.1 Introduction 9.2 The Basic Effects of Hydrostatic Pressure on Biological Systems 9.3 Pressure Stresses and Pressure Adaptations in Biological Systems 9.3.1 Pressure Effects on Dissociation Phenomena 9.3.2 Pressure Effects on Protein Structure 9.3.3 Pressure Effects on Membranes 9.3.4 Pressure Effects on Catalytic Activations 9.3.5 Pressure Effects on Enzyme-Ligand Interactions 9.3.6 Pressure Effects on Transcription and Translation 9.3.7 Mechanisms for Sensing Changes in Pressure 9.4 Concluding CommentsAuthor IndexSubject Index