The Biology of Death: How Dying Shapes Cells, Organisms, and Populations

Description

How does death help us understand the living? Death is more than the last event of life; it is interwoven into our growth, development, protection against disease, and more. It influences the direction of entire species via the cycle of a lifespan, and it involves asking many fascinating questions. How do we differentiate between life and death, though? How do we know when a person, animal, or cell is really dead? How much grey area is there in the science? Why do we age? Can we do anything about it? Scientifically, there's much we can learn about a living thing from its cells. In all living things, cells seem to carry "death" gene programs. Some living organisms have created systems to use these to their own advantage. Humans, for example, use the death of specific cells to hone our immune system and to give us fingernails and hair. Perhaps the most dramatic use occurs during the metamorphosis of insects and frogs. Even single-celled organisms use "quorum sensing" to eliminate some cells to ensure the overall survival of their colony in harsh environments. Thus, there is more to death than just dying. This latest book from science writer Gary C. Howard ties together the many ways that death helps us understand life. He synthesizes the involvement and relation of cells, tissues, organisms, and populations, explaining what happens at the end of life. Between discussions about popular topics such as the ethics of extending life and cell regeneration, Howard also answers fascinating questions about life and death. The resulting book examines how the end of life is determined and what we can learn from this process. Cover Half-Title Title Copyright Dedication About the Dead Man and Fungi Contents Preface 1. Death in Life 2. Defining Life and Death Life: Hard to Define Recognizing Life and Death Bacteria with Synthetic DNA At the Boundary of Living and Nonliving Life, Death, and the Law Where Next? 3. What Kills Humans Mosquitos and Human Death Dying Today Death in the United States Death in the World What Kills Children Today What Do We Believe Kills Us? Death in the Distant Past Death in the More Recent Past Pandemics and Other Large-.Scale Events Looking to the Future: Diseases of Lifestyle 4. Aging and Senescence What Are Aging and Senescence? Physiological Manifestations Does Everything Age? Evolution of Aging Modern Theories of Aging Can We Do Anything About Aging? Aging as a Disease 5. Dying Clinical Signs of Approaching Death What Happens at the Moment of Death and Shortly Thereafter Do All of Our Cells Die at the Same Time? Near-.Death Experiences Keeping Body and Soul Together 6. Ashes to Ashes and Dust to Dust What Happens After Death? When the Heart Stops Understanding the Process Laying the Dead to Rest Other Methods Animals and Death How Plants Decompose 7. Genetics of Life and Death Theories of Aging Based on Genes and DNA Nutrient-.Sensing Mechanisms Worn-.Out Parts Cellular Senescence Cell Signaling Future Directions 8. Death of Cells Life and Death of Cells Cellular Aging and Death Programmed Cell Death Anastasis: A Near-.Death Experience for Cells Metamorphosis 9. Programmed Cell Death in Humans Development Disease and Injury 10. Death in Plants Cell Death Programmed Cell Death Death in Growth and Development Plant Pathogens and Defenses Programmed Cell Death in Plant Diseases 11. Death in Bacteria, Fungi, and Protista Quorum Sensing by Bacteria Fungi Protista 12. Death on a Grand Scale Geology and Biology Defining Mass Extinctions Causes of Mass Extinctions Major Mass Extinction Events Mass Extinctions Now and in the Future 13. Last Hominid Standing What Happened to Our Predecessors? Our Possible Family Members Emergence of Homo sapiens and Interbreeding with Other Hominids Leaving Africa Genetic Bottlenecks and Human Evolution Last of the Hominids 14. Bioethics Who Wants to Live Forever? Treating Current Patients Ethical Questions Research into Aging: General Arguments Bioethical Controversies in Specific Research Areas Aging Research as a Moral Imperative 15. Future of Death New Technologies New Threats Have We Reached the Limit of Human Life Span? Aging as a Disease Predictions Unverified 16. Death Is More than Dying Glossary References Index