Gravity and the Behavior of Unicellular Organisms

Author: Donat-Peter Häder
Publisher: Cambridge University Press
ISBN: 9780521820523
Format: PDF
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Unicellular organisms use gravity as an environmental guide to reach and stay in regions optimal for their growth and reproduction. These single cells play a significant role in food webs and these factors together make the effects of gravity on unicellular organisms a fascinating and important subject for scientific study. In addition, they present valuable model systems for studying the mechanisms of gravity perception, a topic of increasing interest in these days of experimentation in space. This book reveals how single cells achieve the same sensoric capacity as multicellular organisms like plants or animals. It reviews the field, discussing the historical background, ecological significance and related physiology of unicellular organisms, as well as various experimental techniques and models with which to study them. Those working on the biology of unicellular organisms, as well as in related areas of gravitational and space science will find this book of value.

Habitability of the Universe before Earth

Author:
Publisher: Academic Press
ISBN: 0128119411
Format: PDF, ePub, Docs
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Habitability of the Universe before Earth: Astrobiology: Exploring Life on Earth and Beyond (series) examines the times and places—before life existed on Earth—that might have provided suitable environments for life to occur, addressing the question: Is life on Earth de novo, or derived from previous life? The universe changed considerably during the vast epoch between the Big Bang 13.8 billion years ago and the first evidence of life on Earth 4.3 billion years ago, providing significant time and space to contemplate where, when and under what circumstances life might have arisen. No other book covers this cosmic time period from the point of view of its potential for life. The series covers a broad range of topics encompassing laboratory and field research into the origins and evolution of life on Earth, life in extreme environments and the search for habitable environments in our solar system and beyond, including exoplanets, exomoons and astronomical biosignatures. Provides multiple hypotheses on the origin of life and distribution of living organisms in space Explores the diversity of physical environments that may support the origin and evolution of life Integrates contemporary views in biology and cosmology, and provides reasons that life is far more mobile in space than most people expect Includes access to a companion web site featuring supplementary information such as animated computer simulations

Hormones Signals and Target Cells in Plant Development

Author: Daphne J. Osborne
Publisher: Cambridge University Press
ISBN: 9781139443067
Format: PDF, Kindle
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Meristematic cells in plants become the many different types of cells found in a mature plant. This is achieved by a selective response to chemical signals both from neighbouring cells and distant tissues. It is these responses that shape the plant, its time of flowering, the sex of its flowers, its length of survival or progress to senescence and death. How do plants achieve this? This treatise addresses this question using well-chosen examples to illustrate the concept of target cells. The authors discuss how each cell has the ability to discriminate between different chemical signals, determining which it will respond to and which it will ignore. The regulation of gene expression through signal perception and signal transduction is at the core of this selectivity and the Target Cell concept. This volume will serve as a valuable reference for all researchers working in the field of plant developmental biology.

Biological and Medical Research in Space

Author: David Moore
Publisher: Springer Science & Business Media
ISBN: 3642610994
Format: PDF
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Life Science studies in space were initially driven by the need to explore how man could survive spaceflight conditions; the effects of being launched un der high accelerations, exposed to weightlessness and radiation for different periods of time, and returned to Earth in safety. In order to substantiate the detailed knowledge of potentially adverse effects, many model experiments were launched using organisms which ranged from bacteria, plants, inverte brates, rodents and primates through to man. Although no immediate life threatening effects were found, these experiments can be considered today as the precursors to life science research in space. Many unexplained effects on these life forms were attributed to the condition of weightlessness. Most of them were poorly recorded, poorly published, or left simply with anecdotal information. Only with the advent of Skylab, and later Spacelab, did the idea emerge, and indeed the infrastructure permit, weightlessness to be considered as an ex tended tool for research into some fundamental mechanisms or processes as sociated with the effect of gravity on organisms at all levels. The initial hy pothesis to extrapolate from hypergravity through 1 x g to near 0 x g effects could no longer be retained, since many of the experiment results were seen to contradict the models or theories in the current textbooks of biology and physiology. The past decade has been dedicated primarily to exploratory research.

Aerospace Medicine and Biology

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Publisher:
ISBN:
Format: PDF
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A selection of annotated references to unclassified reports and journal articles that were introduced into the NASA scientific and technical information system and announced in Scientific and technical aerospace reports (STAR) and International aerospace abstracts (IAA).

Fundamentals of Space Medicine

Author: Gilles Clément
Publisher: Springer Science & Business Media
ISBN: 9781402034343
Format: PDF, ePub, Mobi
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This readable text presents findings from the life science experiments conducted during and after space missions. It provides an insight into the space medical community and the real challenges that face the flight surgeon and life science investigator.