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Klappentext This is the first detailed treatment of the long-standing! previously unresolved controversy surrounding the nature of senescence in clonal cultures. Part historical review of the literature! part detective story! Sex and Death in Protozoa presents a comprehensive but entertaining discussion of the sometimes contradictory evidence for protozoan senescence and the rejuvenating effects of sex in these organisms. Drawing on Hermann Muller's "ratchet model!" Dr. Bell demonstrates in a quantitative fashion how genetic recombination (an intrinsic part of the sexual process) can eliminate the deleterious effects of accumulated mutations in clonal cultures and provide the rejuvenating effects associated with mating. This well written account by one of the leading authorities in the field is indispensable reading for those interested in the genetics and cell biology of protozoa! and more generally! those researchers and students interested in the phenomenon of senescence. Zusammenfassung In this book Dr Bell disinters and re-analyzes the early 20th-century debate on senescence and death in animals and plants! and argues that protozoan lineages senesce as the result of an accumulated load of mutations that can be shed only through sexual reproduction. Inhaltsverzeichnis List of illustrations; List of tables; Preface; 1. The question of protozoan immortality; 2. Sex and reproduction in ciliates and others; 3. Isolation cultures; 4. The fate of isolate cultures; 5. The culture environment; 6. Does sex rejuvenate?; 7. Germinal senescence in multicellular organisms; 8. The ratchet; 9. Soma and germ; 10. Mortality and immmortality in the germ line; 11. The function of sex; References; Index of first authors; Index of genera; Index of subjects.
