Beschreibung
Why a Book on Paramecium? Biologists usually concentrate their efforts on a single problem and a single organism. There is a difficulty with this practice, however, for as work on a problem proceeds it often becomes more ad vantageous to study the problem in another organism. Some biologists avoid the difficulty by moving from one organism to the other as the problem de mands. However, this tactic also has a disadvantage, for a thorough knowledge of the life cycle and thorough mastery of ways to handle a given organism in the laboratory are obviously of great importance to the researcher, and one can never know several organisms as well as one can know a single one. Another way of doing research is to pick the organism, learn all one can about it from all points of view, and then assess the significance of the findings. Tracy Sonneborn practiced research in very much this way. He would have found virtually every chapter in this volume about Paramecium a fascinating summary of one of his areas of research. Indeed, the beginnings of most of the topics in this book are founded on his studies. With every new fact he learned about Paramecium, he carefully assessed the significance of his findings, not on ly for research on protozoa, but for biology in general. His work, and in a way this book too, are indicative of the success of his strategy.
Inhaltsverzeichnis
Inhaltsangabe1 Introduction.- 2 Cytology (With 35 Figures).- 1 Introduction.- 2 The Pellicle.- 3 Cytoplasmic Organelles.- 4 Cytoplasmic Organelle Systems.- 5 Nucleus.- 6 Symbionts.- References.- 3 The Species Concept and Breeding Systems.- 1 Background.- 2 Updating the Taxonomy and Breeding Systems of Paramecium.- 3 Problems and Future Directions.- References.- 4 Mating-Type Inheritance (With 1 Figure).- 1 Introduction.- 2 Genetic Basis of Mating-Type Inheritance.- 3 Macronuclear Differentiations for the Expression of Mating Type.- 4 Genetic Control of Mating-Type Substances.- References.- 5 Conjugation (With 1 Figure).- 1 Introduction.- 2 Induction of Conjugation.- 3 Cell Surface Events in Conjugation.- 4 Nuclear Events in Conjugation.- 5 Perspectives.- References.- 6 Mating-Type Substances.- 1 Introduction.- 2 Role of Mating-Type Substances in Conjugation.- 3 Chemical Nature of the Mating-Type Substances.- 4 Recent Advances in Biochemical and Immunological Studies on the Mating-Type Substances.- 5 Conclusion.- References.- 7 The Cell Cycle and Regulation of Cell Mass and Macronuclear DNA Content (With 10 Figures).- 1 Introduction.- 2 Patterns of Growth, Replication and Morphogenesis.- 3 Control of Cell Cycle Events.- 4 Quantitative Regulation of Cell Components.- 5 Comparison with Other Organisms.- References.- 8 Nuclear Dimorphism and Function.- 1 Introduction.- 2 Nuclear Function During Vegetative Phase.- 3 Nuclear Function During Sexual Cycle.- References.- 9 Aging.- 1 Mortal or Immortal.- 2 Life Cycle Stages.- 3 Fission Life Span or Calendar Life Span.- 4 Nuclear or Cytoplasmic.- 5 Programmed or Error Accumulated.- References.- 10 Organization and Expression of the Nuclear Genome.- 1 Introduction.- 2 Nuclear Dimorphism.- 3 DNA Structure.- 4 Chromatin Structure and Chromosomal Proteins.- 5 Transcription of the Macronuclear Genome.- 6 The Genetic Code.- 7 Conclusions and Summary.- References.- 11 Immobilization Antigens.- 1 Introduction.- 2 Serotypes.- 3 Serotype Transformation.- 4 Localization and Possible Functions.- 5 Chemistry and Molecular Biology of i-Antigens.- 6 Conclusion.- References.- 12 Mitochondria (With 6 Figures).- 1 Introduction.- 2 Genetics.- 3 Respiratory Chain.- 4 Molecular Biology of the Genome.- References.- 13 Electrophysiology (With 4 Figures).- 1 Introduction.- 2 A Historical Note.- 3 Ion Batteries and Membrane Channels.- 4 Properties of the Resting Membrane.- 5 Responses to Stimuli.- 6 Voltage-Dependent Responses.- 7 Topology of Ion Channels.- 8 Conclusion.- References.- 14 Motor Control of Cilia (With 6 Figures).- 1 Introduction.- 2 Galvanotaxis: A Classic Reviewed.- 3 Current Methods.- 4 The Cilium is a Rotary Sliding Machine.- 5 Parameters of Ciliary Activity.- 6 Reactivation of Ciliary Axonemes.- 7 Depolarization-Induced Ciliary Activity (DCA).- 8 Hyperpolarization-Induced Ciliary Activity (HCA).- 9 Adaptation.- 10 Steps in Electromotor Coupling.- 11 Perspectives.- References.- 15 A Genetic Dissection of Ion-Channel Functions (With 8 Figures).- 1 Introduction.- 2 Ion Currents.- 3 Mutants with Defective Currents.- 4 The Use of the Mutants.- 5 A Search for the Gene Products.- 6 Conclusion.- References.- 16 Biochemistry of Cilia (With 5 Figures).- 1 Introduction.- 2 Axenic Mass Culture of Paramecium.- 3 Ciliary Surface Proteins.- 4 Ciliary Lipid Composition.- 5 Ciliary Membrane Proteins.- 6 Axonemal Dynein ATPases.- References.- 17 Behavioral Genetics in P. caudatum (With 2 Figures).- 1 Introduction.- 2 Outline of P. caudatum Genetics and Isolation of Recessive Mutants.- 3 Behavioral Mutants.- 4 Relation of CNRs to Pawns in P. tetraurelia.- 5 Genic and Allelic Interactions of CNR Loci Observed in P. caudatum.- 6 Conclusion.- References.- 18 Chemokinesis (With 7 Figures).- 1 Introduction.- 2 Assays of Chemoresponse.- 3 Swimming behavior.- 4 Stimuli.- 5 Chemoreceptors.- 6 Characteristic Membrane Potential Changes in Chemoresponse: Models for Testing.- 7 Second Messengers.- 8 Summary.- References.- 19 The Lysosom
