eBooks de Biología, página 33 de 128

Si algo distingue realmente a la Bioquímica del resto de las disciplinas químicas, es el papel central que en los seres vivos desempeñan las enzimas. Y si algún elemento distintivo hay en la Bioquímica frente a las ciencias biologicas es que las enzimas nos brindan un modelo interpretativo de uso general para todas ellas sin excepcion en terminos de la teoria atomico-molecular. El estudio de las biomoleculas no es en si mismo mas que una serie de capitulos de la Quimica Organica, por mas que se utilicen tecnicas poco convencionales desde el punto de vista de esta ciencia. Lo realmente unico en la quimica biologica es esa impresionante cantidad de catalizadores especificos encargados cada uno de un determinado proceso dentro de los muchos miles de reacciones quimicas posibles en los organismos. ¿Como son las enzimas? ¿Como funcionan? ¿Como se forman? La respuesta a estas preguntas, entendidas en su mas amplio significado, nos brindaria la explicacion a todos los fenomenos que asociamos a la vida: la posibilidad de un metabolismo; de su regulacion, y por tanto de su integracion a un nivel fisiologico; igualmente, de su biosintesis y todos los fenomenos geneticos a ella asociados; y por ultimo, de las complicadas pautas evolutivas y adaptativas de los organismos vivientes. No es de extrañar, por tanto, que los espectaculares avances de la Bioquimica habidos en los ultimos treinta años hayan tenido lugar normalmente en torno a sistemas experimentales nacidos del estudio convencional de las enzimas. Los metodos y tecnicas de purificacion y aislamiento de enzimas han marcado las pautas de toda la Bioquimica preparativa o extractiva; los metodos que la Enzimologia emplea en la cuantificacion de enzimas forman la base de la Bioquimica Analitica, habiendo transcendido su uso al Analisis Quimico General; el estudio quimico de los inhibidores ha creado los protocolos que hoy se siguen en el desarrollo sistematico de nuevos farmacos. Y ya en la esfera puramente teorica, el estudio de las reacciones enzimaticas nos ha suministrado un modelo de aplicacion general a todas las interacciones biologicas; el de un ligando uniendose a un receptor de naturaleza proteica, y desencadenando en el un cambio que es el ultimo responsable molecular del efecto fisiologico investigado. Por otra parte, el estudio cinetico de cadenas de reacciones enzimaticas nos va dando una idea, hoy todavia aproximada, de las complejidades dinamicas que pueden surgir en el ser vivo por la accion de las enzimas, y que en un terreno puramente especulativo podemos relacionar sin demasiada dificultad con cuestiones tan abstractas como el origen objetivo del tiempo biologico o las asimetrias (y simetrias) espaciales que surgen en la ontogenia de los seres vivos. En el momento actual quiza es posible que el termino Enzimologia pueda sonar un tanto pasado de moda, sobre todo en comparacion con otros como Biotecnologia o Ingenieria Genetica, y que nos recuerde los viejos laboratorios donde se hacia Bioquimica clasica alla por los años 50 y 60. Por ello trato de reivindicar la importancia de la misma. Si la Biotecnologia no es otra cosa que introducir en gran escala a las enzimas en el proceso productivo y economico, la Ingenieria Genetica actual no es concebible sin la ayuda de una serie muy concreta de enzimas; y ademas, sus ultimas aspiraciones son enteramente enzimaticas: la introduccion de nuevos procesos metabolicos alla donde normalmente no los hay. La Genetica Molecular se ocupa de los planos del edificio viviente; la Enzimologia, del estudio del propio edificio funcionando. El proposito del autor de este libro es presentar una vision actualizada de las enzimas, pero a un nivel de estudiante de Grado, y especificamente, en el area de Ciencias de la Salud. Para el especialista hay numerosas y magnificas monografias, aparte de series perio...

Si estamos de acuerdo que el paisaje puede ser objeto de conocimiento histórico debemos vincularlo –para su estudio- a otros elementos como son las diferentes sociedades que lo gestionaron o el uso q

Hormones animate every aspect and every moment of our lives, controlling our milestone moments as well as our day-to-day emotions and behaviour. Dr Saira Hameed is one of the UKs leading endocrinologists and in Signals she invites us into her clinic to see the lives interrupted by misfiring hormones and how fixing the problem recalibrates a life.We sit beside Dr Hameed as she hears stories from spirit-sapping exhaustion to agonising infertility, absent libido to frenzied disorientation. We see an emaciated girl who is close to death and another battling obesity. We meet a young boy who cant stay awake and a teenage girl a whose racing heart will not be able to keep going much longer.Signals takes us on a journey inside our bodies to reveal the spectacular endocrine life force at work. Combining compassionately told patient histories, with stories of pioneering medical breakthroughs and addressing common misconceptions and hormone hacks, this is a vital book for anyone who wants to understand their health and their happiness and to appreciate the wonder that to be human is to be hormonal too.

Many people as they get older have to face leaving a village or town they have loved, a place redolent with memories and connections, to relocate somewhere more as they say manageable. It is different for everyone, and not always easy, for our ghosts go with us.But everything connects with everything else. There is no such thing as a new beginning. Such a move need not be a matter for repining and regret, but a new adventure.This book records just that journey, of having to learn that new place to which Time is bringing you and populate it with its own stock of private memories.Charles Moseley writes about his move from a fenland village to the nearby historic little city of Ely and breathes life into the history, natural world and people who have made his new home what it is today.

Gods Providential Work in Creation Before Life Began God has been present and active in creation from the moment he created it ex nihilo. Few Christians would question this claim, but its implications for ongoing theology and science dialogues have not been fully explored.In this pathbreaking and field-advancing work, Ross Hastings brings his expertise in both scientific and theological disciplines to bear on the topic of divine providence in chemical evolution. Based on the latest research in the developing field of chemical evolution and the work of theological giants such as Karl Barth, Hastings shows how God may have been providentially and non-competitively at work in the process by which simple prebiotic molecules gave rise to the complex molecules in the first living organisms.In God and Molecules, Hastings provides cutting-edge theological engagement with the developing scientific field of chemical evolution, advances the discussion in theology and science with this new integrative work, and offers a holistic alternative for thinking about chemical evolution that overcomes the binary of theology versus science. God and Molecules pushes toward new frontiers in theology and science and casts a compelling, integrative, and ultimately healing vision for how God has been lovingly involved in the developmental process of the earliest life on earth.

As belíssimas colagens de Geraldo Valério retratam em todo o seu colorido conhecidas flores brasileiras da nossa flora, abrindo nossos olhos para a observação da natureza e para a apreciação do traba

Where the land meets the sea, life clings to the margins in a world of relentless change. The intertidal zone is a place of extremes - where creatures endure crashing waves, scorching sun, and the constant ebb and flow of the tides. It is a place of resilience and adaptation and home to some of the most extraordinary organisms on the planet.Blending marine biology, oceanography and evolutionary science, marine biologist Ruth Searle takes us on a journey through the deep history of the intertidal zone - from its ancient origins as the possible cradle of life to the remarkable adaptations of the species that inhabit it today. Exploring the geological forces that shape coastlines, the mechanics of tides and waves, and the evolutionary arms race that has unfolded on the shore, this book reveals how the intertidal zone has not only survived mass extinctions but has driven some of natures most extraordinary innovations.The Intertidal Zone: Life on the Edge is a celebration of one of Earths most dynamic ecosystems - its beauty, its mysteries, and its fragility. As climate change and human activity reshape coastlines across the planet, understanding this environment has never been more urgent.

Keeping yourself and your horse safe is key to enjoying riding, wherever you are. This Ride Safe Guide is packed full of tips, guidance and practical examples to give you peace of mind that you have the knowledge and know-how to stay safe when out and about with your horse. From hacking to competing, this handy guide covers everything you may encounter while out riding, or carriage driving. The Ride Safe Guide will support you as you train for your BHS Ride Safe Award where youll learn about: riding safely on and off-road including farmland and beaches, managing hazards, communicating with other route users and much more. Whether youre enjoying a peaceful countryside hack or warming up for competition, our Ride Safe Award will give you all the key skills you need. British Horse Society offers a wide range of equestrian qualifications and awards, from foundation through to performance level. Gain a world-leading standard of qualification from a provider you can trust. For horses. For people. For life.

Micrographia is a historic book by Robert Hooke, detailing the then thirty-year-old Hookes observations through various lenses. Published in September 1665, the first major publication of the Royal Society, it was the first scientific best-seller, inspiring a wide public interest in the new science of microscopy. It is also notable for coining the biological term cell.Observations:Hooke most famously describes a flys eye and a plant cell (where he coined that term because plant cells, which are walled, reminded him of a monks quarters). Known for its spectacular copperplate engravings of the miniature world, particularly its fold-out plates of insects, the text itself reinforces the tremendous power of the new microscope. The plates of insects fold out to be larger than the large folio itself, the engraving of the louse in particular folding out to four times the size of the book. Although the book is best known for demonstrating the power of the microscope, Micrographia also describes distant planetary bodies, the wave theory of light, the organic origin of fossils, and various other philosophical and scientific interests of its author.

"De cegueira em cegueira, eliminamos tanta vida do nosso horizonte intelectual que, no fim, ficamos sozinhos." Em Fitópolis, o neurobiólogo e botânico italiano Stefano Mancuso propõe uma transformaçã

The book that changed the way we see life on Earth.Charles Darwins On the Origin of Species introduces the revolutionary theory of natural selection, explaining how species evolve over time through adaptation and survival. The 6th edition reflects Darwins refined observations and includes essential updates that shaped modern biology.Accessible, compelling, and timeless, this scientific classic continues to inspire scholars, students, and curious minds around the world, offering profound insight into the natural world and our place within it.Discover the foundation of evolutionary sciencedownload On the Origin of Species, 6th Edition today and explore Darwins groundbreaking work.

Il saggio tocca piu o meno brevemente e del tutto liberamente numerosissimi temi culturali e sociali proposti singolarmente, fuori da ogni sistematicita, talora esposti in forma aforistica, ma che valutati tutti insieme formano una visione del mondo ampia e coerente nelle sue coordinate di base, tale che mai annoia e sempre invoglia a proseguire nella lettura. Un importante assunto ne sta alla base, il metodo scientifico esclude il pregiudizio in qualsiasi ambito esso si esplichi. Si tratta di riflessioni dellAutore sul senso della vita reale e concreta, sulleternita, sulla fisica, su Dio e sugli dei, su eventi storici importanti del passato, sul presente sociopolitico di vari paesi, sulle donne, sugli uomini, sullevoluzione, lecologia la natura su moltissimo altro, innumerevoli spunti di pensiero. Una filosofia essenziale e concreta, il libro e un utile strumento di stimolo.

Are you affected by Epstein-Barr Virus or a family member? Do you want to learn everything about this disease and put the virus on its knees? Then this book is exactly what you need! The Epstein-Barr virus is a disease that should not be taken lightly. The virus can weaken the immune system and pave the way for other bacteria and pathogens. As of current knowledge, there are no vaccines or medications, but there are other ways to bring the virus to its knees. In this book, you will learn how to chain the virus and drastically improve your quality of life.What to expect: What is Epstein-Barr virus? What it is not? Symptoms and personal experiences Current scientific status, vaccines & diagnostics Holistic treatment of Epstein-Barr Alternative healing approaches and much more...Buy this book now and chain the virus down!

A monumental compilation of zoological data, this text describes the anatomy, behavior, and habitats of hundreds of animal species. Aristotle classifies animals based on their modes of reproduction, diet, and physical differences, looking for patterns in natures diversity. The observations range from the embryology of birds to the habits of marine life, showcasing a keen empirical eye. It establishes biology as a systematic science, grounded in observation and the comparison of living forms.

In the following pages an attempt has been made to emphasize the value of Embryology and Comparative Anatomy in elucidating the difficult and often complicated morphological problems encountered in the study of human adult anatomy.Moreover, in addition to the direct advance in the method and scope of anatomical teaching afforded by these aids, it is further hoped that the broader interpretation, both of structure and function, obtained by ontogenetic and phylogenetic comparison, will impart an interest to the study of adult human morphology, such as the subject, considered solely in the narrow field of its own limitations, could never arouse.The book represents part of the course in visceral anatomy as developed during the past fourteen years at Columbia University. The sections dealing with the morphology of the vertebrate ileo-colic junction and with the structural details of the human ccum and appendix are considered somewhat more fully, as warranted by the extensive material available. The illustrations are for the greater part taken from preparations in the Morphological Museum of the University.

A few lines will suffice to explain why we have compiled the present volume, to what wants it responds, and what its sphere of usefulness may possibly embrace.In our teaching of plastic anatomy, especially at the Ecole des Beaux-Artswhere, for the past nine years, we have had the very great honour of supplementing the teaching of our distinguished master, Mathias Duval, after having been prosector for his course of lectures since 1881it is our practice to give, as a complement to the study of human anatomy, a certain number of lessons on the anatomy of those animals which artists might be called on to represent.Now, we were given to understand that the subject treated in our lectures interested our hearers, so much so that we were not surprised to learn that a certain number repeatedly expressed a desire to see these lectures united in book form.Edouard CuyerGENERALITIES OF COMPARATIVE ANATOMYOf the animals by which we are surrounded, there are some which, occupying a place in our lives by reason of their natural endowments, are frequently represented in the works of artistseither as accompanying man in his work or in his amusements

An Inquiry into the Nature and Causes of the Wealth of Nations, generally referred to by its shortened title The Wealth of Nations, is the magnum opus of the Scottish economist and moral philosopher Adam Smith. First published in 1776, the book offers one of the worlds first collected descriptions of what builds nations wealth, and is today a fundamental work in classical economics. By reflecting upon the economics at the beginning of the Industrial Revolution, the book touches upon such broad topics as the division of labour, productivity, and free markets.The Wealth of Nations was published 9 March 1776, during the Scottish Enlightenment and the Scottish Agricultural Revolution. It influenced several authors and economists, such as Karl Marx, as well as governments and organisations, setting the terms for economic debate and discussion for the next century and a half. For example, Alexander Hamilton was influenced in part by The Wealth of Nations to write his Report on Manufactures, in which he argued against many of Smiths policies. Hamilton based much of this report on the ideas of Jean-Baptiste Colbert, and it was, in part, Colberts ideas that Smith responded to..

Aristotle compiles a massive encyclopedia of zoological observations, cataloging the differences and similarities between hundreds of species. The text focuses on the functional anatomy of animals, their reproductive methods, and their behaviors in the wild. It represents the birth of biology as an empirical science, moving from anecdote to systematic classification. The work demonstrates a profound curiosity about the natural world, seeking to find order and purpose in the diversity of life.

Criar peixes de estimação é um dos hobbies mais gratificantes e relaxantes, mas os cuidados adequados vão muito além de simplesmente encher um aquário com água. Este e-book é um guia prático e acessí

Prezado(a) Amigo(a),Você está pensando em adquirir um novo animal de estimação para sua família? Talvez esteja considerando várias possibilidades diferentes, ou talvez já tenha decidido que um pássar