The Genetic Mechanism and the Origin of Life

1. Origins of Life's Ingredients.- 1.1. The Setting.- 1.2. Prebiotic Syntheses (Stage I).- 1.3. Prebiotic Polymerization (Stage II).- 1.4. Summary.- 2. The Precellular, or Simple Interacting Systems, Level (Stage III).- 2.1. Synthetic Models of Protobionts.- 2.2. Autocatalysis.- 2.3. The Present Status of the Life Origins Problem-A Critical Assessment.- 3. The Genetic Mechanism: I. DNA, Nucleoids, and Chromatin.- 3.1. Introduction.- 3.2. The Focal Ingredients.- 3.3. The Key Macromolecule.- 3.4. Replication of DNA.- 3.5. Chromatin and the Chromosome.- 4. The Genetic Mechanism: II. the Cell's Employment of DNA.- 4.1. The Types of Ribonucleic Acid.- 4.2. Translation and Protein Synthesis.- 5. The Genetic Mechanism: III. Transcription, Processing, and an Analytical Synopsis.- 5.1. Transcription of the DNA Molecule.- 5.2. An Alternative Protein-Synthesizing System.- 5.3. An Annotated Synopsis-Summary and Analysis.- 6. Micromolecular Evolution-The Origin of the Genetic Code.- 6.1. Conceptual Approaches.- 6.2. Mathematical Concepts.- 6.3. Biochemical Approaches.- 6.4. A Biological Concept.- 7. The Transfer Ribonucleic Acids.- 7.1. The Characteristic Molecular Features of tRNAs.- 7.2. Codon-Anticodon Interactions.- 7.3. Summary of tRNA Structural Features.- 8. Reactive Sites and the Evolution of Transfer RNAs.- 8.1. Reactive Sites of tRNAs.- 8.2. Evolutionary Relations of tRNAs.- 8.3. Origin and Evolution of tRNA.- 9. The Genetic Mechanism of Viruses.- DNA Viruses.- 9.1. Double-Stranded DNA Viruses.- 9.2. Single-Stranded DNA Viruses.- RNA Viruses.- 9.3. Single-Stranded RNA Viruses.- 9.4. Double-Stranded RNA Viruses.- Proteinaceous Viruses.- Summary and Conclusions.- 10. The Origin of Early Life.- 10.1. A Preliminary Definition of Life.- 10.2. The Distinctive Characteristics of Viruses.- 10.3. Possible Steps in the Origins of Early Life.- References.