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Summary: Azoospermia, defined as the absence of sperm in the ejaculate after examination of the centrifuged specimens, affects about 1% of the male population and 10-15% of infertile men. In about two-thirds of cases, this is caused by severe spermatogenic dysfunction, and it is commonly termed "nonobstructive azoospermia" (NOA) to differentiate it from the less severe form of azoospermia caused by the obstruction of the seminal tract (obstructive azoospermia-OA), the latter affecting the remaining one-third of cases. Managing patients with NOA is challenging due to the severity of spermatogenic dysfunction and the lack of medical treatments, with surgical retrieval of testicular sperm being the only way of enabling some of these patients to father their own biological children. In-depth clinical knowledge is key for supporting clinical reasoning and decision making when counselling patients with NOA, and surgical skill is required to maximize the outcome of surgical procedures that aim to retrieve testicular sperm. The present book is a collection of scientific papers published in a Special Issue of the Journal of Clinical Medicine, authored by some of the most influential researchers in the field. The Special Issue, and thus also this book, were conceived to provide early career reproductive urologists and endocrinologists with an update of the scientific evidence in the field, together with surgical tips.

What's in Your Genome? describes the functional regions of the human genome, the evidence that 90% of it is junk DNA, and the reasons this evidence has not been widely accepted by the popular press and much of the scientific community. The human genome contains about 25,000 protein-coding and noncoding genes and many other functional elements, such as origins of replication, regulatory elements, and centromeres. Functional elements occupy only about 10 percent of the more than three billion base pairs in the human genome. Much of the rest is composed of ancient fragments of broken genes, transposons, and viruses. Almost all of this is thought to be junk DNA, based on evidence that dates back fifty years. This conclusion is controversial. What's in Your Genome? describes the arguments on both sides of the debate and attempts to explain the reasoning behind those different points of view. The book corrects a number of false narratives that have arisen in recent years and examines how they have affected the debate over junk DNA. In addition, Laurence A. Moran focuses on scientific misconceptions and misinformation and on how the junk DNA controversy has been incorrectly portrayed in both the scientific literature and the popular press. Tracing the earliest indications of junk DNA back to the 1960s, the book explains the success of nearly neutral theory and the importance of random genetic drift, which gave rise to the view that evolution produces sloppy genomes full of junk DNA. What's in Your Genome? aims to offer the most accurate and current account of the human genome.

Extensively reorganized and revised with the latest data from this rapidly changing field, Lewin's Essential GENES, Third Edition, provides students with a comprehensive overview of molecular biology and molecular genetics.

This whistlestop guide teaches you everything you need to know about the fascinating science of genetics! Genetics is the study of heredity, and reveals how the characteristics of living organisms are determined by the genes passed down the generations. In humans, it can determine how we think,who we are, and how long we live. The human genome was mapped in 2003, and this enhanced ability to study our genes is transforming medicine, from CRISPR, the gene editing technology that allows us to alter the course of hereditary disease, to using genetics to identify the types of bacteria that populate our bodies. Stripping the subject to its bare necessities,30-Second Genetics charts the most extraordinary discoveries, from the fundamentals of cell biology to the almost unbelievable advances in DNA sequencing and stem cell technology. Each subject, concept or term is explored in a mere 30 seconds, 300 words, and one image, making this the perfect book to understand the field of genetics at lightening speed! Authors (and identical twin brothers) Jonathan and Matthew Weitzman are both expert professors in the field, and they write with clarity, exploring these complicated terms in easy to understand language. From advances in stem cell therapy to animal cloning, genetically modified crops and genetically tailored treatments, the Weitzman brothers demystify this essential science which is shaping our future, today!

From the Pulitzer Prize-winning, bestselling author of The Emperor of All Maladies – a magnificent history of the gene and a response to the defining question of the future: What becomes of being human when we learn to “read” and “write” our own genetic information? Siddhartha Mukherjee has a written a biography of the gene as deft, brilliant, and illuminating as his extraordinarily successful biography of cancer. Weaving science, social history, and personal narrative to tell us the story of one of the most important conceptual breakthroughs of modern times, Mukherjee animates the quest to understand human heredity and its surprising influence on our lives, personalities, identities, fates, and choices. Throughout the narrative, the story of Mukherjee's own family – with its tragic and bewildering history of mental illness – cuts like a bright, red line, reminding us of the many questions that hang over our ability to translate the science of genetics from the laboratory to the real world. In superb prose and with an instinct for the dramatic scene, he describes the centuries of research and experimentation – from Aristotle and Pythagoras to Mendel and Darwin, from Boveri and Morgan to Crick, Watson and Franklin, all the way through the revolutionary twenty-first century innovators who mapped the human genome. The Gene is a must-read for everyone concerned about the definition and future of humanity. This is the most crucial science of our time, intimately explained by a master.

Genes were unknowingly discovered in the 19th century by Gregor Mendel, a Czechoslovakian monk. It was later established that genes are made of DNA, a biological compound found in tiny thread-like structures called chromosomes that are located in the nuclei of all cells in our bodies. DNA consists of chains of entities called bases of which there are four in nature. DNA consists of long chains of bases (sometimes referred to as DNA sequences) that are joined in any order, but the precise order and length of which constitute different genes.Many (but not all) genes carry a code called the genetic code, a code that instructs the synthesis (manufacture) of the many hundreds of proteins that we require to survive and execute the many functions of life. The genetic code was deciphered in relatively recent years and is considered one of the most significant discoveries in the history of biology.Genes that encode instructions for the synthesis of proteins and those that regulate the manufacture of proteins comprise a mere two percent of our DNA. Despite our extensive knowledge of biology and the sub-discipline of molecular biology (the study of biology at the molecular level), the function (if any) of the rest of the DNA in our cells is unknown.Research about genes and DNA has in recent years spawned an endeavor referred to as the Human Genome Project, an international collaboration that has successfully determined, stored, and rendered publicly available the sequences of almost all the genetic content of the chromosomes of the human organism, otherwise known as the human genome.DNA sequences that are unique to every person on earth have been discovered (DNA fingherprints) and are now used for identifying criminals. The book relates a specific example of identifying a criminal who murdered two women.This is the first and only book that we are aware of that educates non-biologists about genes. It is written in a style and uses a vocabulary that can be comprehended by the average reader who knows very little if anything about genes.

This book focuses on the latest genome sequencing of the 25 wild Oryza species, public and private genomic resources, and their impact on genetic improvement research. It also addresses the untapped reservoir of agronomically important traits in wild Oryza species. Rice is a model crop plant that is frequently used to address several basic questions in plant biology, yet its wild relatives offer an untapped source of agronomically important alleles that are absent in the rice gene pool. The genus Oryza is extremely diverse, as indicated by a wide range of chromosome numbers, different ploidy levels and genome sizes. After a 13-year gap from the first sequencing of rice in the 2002, the genomes of 11 wild Oryza species have now been sequenced and more will follow. These vast genomic resources are extremely useful for addressing several basic questions on the origin of the genus, evolutionary relationships between the species, domestication, and environmental adaptation, and also help to substantiate molecular breeding and pre-breeding work to introgress useful characters horizontally from wild species into cultivated rice.

Now in its twelfth edition, Lewin's GENES continues to lead with new information and cutting-edge developments, covering gene structure, sequencing, organization, and expression. Leading scientists provide revisions and updates in their individual field of study offering readers current data and information on the rapidly changing subjects in molecular biology.

T-box Genes in Development and Disease looks at the genes encoding the T-box family of transcription factors function as key regulators of many important decision processes during embryonic and tissue development. The importance of these genes is further underlined by the fact that most members of this gene family have been conserved during evolution from worms to humans. This book brings together the current information on conserved aspects with the evolutionary innovations of the functions of these genes during developmental regulation in various animal species and then discusses their important roles in human disease. Brings together current knowledge from a wide variety of animal species and humans Presents commentary from authoritative experts, and includes many prominent scientists and their research Illuminates the connections between developmental biology, evolution, and human disease Allows researchers and newcomers to this research area to gain a thorough picture of the current knowledge

Few concepts played a more important role in twentieth-century life sciences than that of the gene. Yet at this moment, the field of genetics is undergoing radical conceptual transformation, and some scientists are questioning the very usefulness of the concept of the gene, arguing instead for more systemic perspectives. The time could not be better, therefore, for Hans-Jörg Rheinberger and Staffan Müller-Wille's magisterial history of the concept of the gene. Though the gene has long been the central organizing theme of biology, both conceptually and as an object of study, Rheinberger and Müller-Wille conclude that we have never even had a universally accepted, stable definition of it. Rather, the concept has been in continual flux—a state that, they contend, is typical of historically important and productive scientific concepts. It is that very openness to change and manipulation, the authors argue, that made it so useful: its very mutability enabled it to be useful while the technologies and approaches used to study and theorize about it changed dramatically.

This book examines the visual representations used in the popular communication of genetics. Drawing upon public science communication theories, information design theories, and social semiotics, the book offers both in-depth analyses and high-level synthesis of how genetics is visualized for the U.S. public from the early 20th century to the present. Individual chapters focus on six visual genres: photographs, micrographs, illustrations, genetic code images, quantitative graphs, and molecular structure images. Han Yu challenges readers to consider the significance of these images we often take for granted, including their historical contexts, scientific backstories, information richness, stylistic choices, economic motivations, and social implications. In doing so, the book reveals the complex cognitive, affective, and social-cultural factors that both shape and are shaped by these images. The book will be particularly useful to scholars of public science communication and visual communication, practitioners of science communication, and scientists from a range of related life science disciplines.

This volume focuses on virus-host cell interactions, cellular genes acquired or modulated by viruses, the pathological effects of these interactions, and therapeutic interventions. Several chapters specifically address the role of viruses and genes – such as oncogenes, proto-oncogenes, or tumor suppressor genes – in the etiology of human cancer. Oncogenic signaling by PI3 kinase, mTOR, Akt, or the major cancer drivers MYC and RAF, and the role of tumor suppressors like p53, are discussed in detail. The volume also explores the emerging role of noncoding RNAs such as microRNAs in tumorigenesis and cancer therapeutics, and offers new insights into the role of HIV-host interactions relevant to pathogenesis and treatment. Gathering contributions written by leading scientists in their respective fields, the volume offers a valuable resource for researchers and clinicians alike.

The #1 NEW YORK TIMES Bestseller The basis for the PBS Ken Burns Documentary The Gene: An Intimate History Now includes an excerpt from Siddhartha Mukherjee's new book Song of the Cell! From the Pulitzer Prize–winning author of The Emperor of All Maladies—a fascinating history of the gene and “a magisterial account of how human minds have laboriously, ingeniously picked apart what makes us tick” (Elle). “Sid Mukherjee has the uncanny ability to bring together science, history, and the future in a way that is understandable and riveting, guiding us through both time and the mystery of life itself.” —Ken Burns“Dr. Siddhartha Mukherjee dazzled readers with his Pulitzer Prize-winning The Emperor of All Maladies in 2010. That achievement was evidently just a warm-up for his virtuoso performance in The Gene: An Intimate History, in which he braids science, history, and memoir into an epic with all the range and biblical thunder of Paradise Lost” (The New York Times). In this biography Mukherjee brings to life the quest to understand human heredity and its surprising influence on our lives, personalities, identities, fates, and choices. “Mukherjee expresses abstract intellectual ideas through emotional stories…[and] swaddles his medical rigor with rhapsodic tenderness, surprising vulnerability, and occasional flashes of pure poetry” (The Washington Post). Throughout, the story of Mukherjee's own family—with its tragic and bewildering history of mental illness—reminds us of the questions that hang over our ability to translate the science of genetics from the laboratory to the real world. In riveting and dramatic prose, he describes the centuries of research and experimentation—from Aristotle and Pythagoras to Mendel and Darwin, from Boveri and Morgan to Crick, Watson and Franklin, all the way through the revolutionary twenty-first century innovators who mapped the human genome. “A fascinating and often sobering history of how humans came to understand the roles of genes in making us who we are—and what our manipulation of those genes might mean for our future” (Milwaukee Journal-Sentinel), The Gene is the revelatory and magisterial history of a scientific idea coming to life, the most crucial science of our time, intimately explained by a master. “The Gene is a book we all should read” (USA TODAY).

This book explores the double coding property of DNA, which is manifested in the digital and analog information types as two interdependent codes. This double coding principle can be applied to all living systems, from the level of the individual cell to entire social systems, seen as systems of communication. Further topics discussed include the ubiquitous problem of logical typing, which reflects our inherent incapacity to simultaneously perceive discontinuity and continuity, the problem of time, and the peculiarities of autopoietic living systems. It is shown that the scientific “truths” that appear to be coherent constructions connecting the scientifically verified observations by the rules of logic are in fact always relative and never absolute.

The history of the CCR5 gene as a lens through which to view such issues as intellectual property, Big Pharma, personalized medicine, and race and genomics.In The Genealogy of a Gene, Myles Jackson uses the story of the CCR5 gene to investigate the interrelationships among science, technology, and society. Mapping the varied “genealogy” of CCR5—intellectual property, natural selection, Big and Small Pharma, human diversity studies, personalized medicine, ancestry studies, and race and genomics—Jackson links a myriad of diverse topics. The history of CCR5 from the 1990s to the present offers a vivid illustration of how intellectual property law has changed the conduct and content of scientific knowledge, and the social, political, and ethical implications of such a transformation.The CCR5 gene began as a small sequence of DNA, became a patented product of a corporation, and then, when it was found to be an AIDS virus co-receptor with a key role in the immune system, it became part of the biomedical research world—and a potential moneymaker for the pharmaceutical industry. When it was further discovered that a mutation of the gene found in certain populations conferred near-immunity to the AIDS virus, questions about race and genetics arose. Jackson describes these developments in the context of larger issues, including the rise of “biocapitalism,” the patentability of products of nature, the difference between U.S. and European patenting approaches, and the relevance of race and ethnicity to medical research.

Who Discovered Natural Selection? explains how scientists worked out the way in which living things evolve.

Between the Lines of Genetic Code lays out methodologies and tools for the measurement and evaluation of gene-gene and gene-environment studies and gives perspective on the future of this discipline. The book begins by defining terms for interaction studies, describing methodologies, and critically assessing the viability of current study designs and the possibilities for integrating designs. It then provides recent applications data with case studies in rheumatoid arthritis, multiple sclerosis, myositis and other complex human diseases. Last, it examines current studies and directions for future applications in patient care. Recent multivariate studies show that gene-gene and gene-environment interactions can explain significant variances in inheritance that have previously been undetectable in univariate analysis. These links among genes and between genes and their environments during the development of diseases may serve as important hints for understanding pathogenic mechanisms and for developing new tools for prognosis, diagnosis, and treatment of various diseases. Systematically integrates methods of defining and detecting gene interactions to provide an overview of the field Critically analyzes current methods and tools to aid researchers in integrating gene interaction studies Includes examples of current biomedical applications and presents current research expected to shape clinical research in the near future

Molecular Biology is a rapidly advancing field with a constant flow of new information and cutting-edge developements that impact our lives. Lewin's GENES has long been the essential resource for providing the teaching community with the most modern presentation to this dynamic area of study. GENES XI continues this tradition by introducing the most current data from the field, covering gene structure, sequencing, organization, and expression. It has enlisted a wealth of subject-matter experts, from top institutions, to provide content updates and revisions in their individual areas of study. A reorganized chapter presentation provides a clear, more student-friendly introduction to course material than ever before. - Updated content throughout to keep pace with this fast-paced field. - Reorganized chapter presentation provides a clear, student-friendly introduction to course material. - Expanded coverage describing the connection between replication and the cell cycle is included, and presents eukaryotes as well as prokaryotes. - Available with new online Molecular Biology Animations. - Online access code for the companion website is included with every new book. The companion website offers numerous study aids and learning tools to help students get the most out of their course. - Instructor's supplements include: PowerPoint Image Bank, PowerPoint Lecture Slides, and Test Bank.

Identifying causal genes underlying susceptibility to human disease is a problem of primary importance in the post-genomic era and in current biomedical research. Recently, there has been a paradigm shift of such gene-discovery efforts from rare, monogenic conditions to common'oligogenic'or'multifactorial'conditions such as asthma, diabetes, cancers and neurological disorders. These conditions are referred to as multifactorial because, susceptibility to these diseases is attributed to the combinatorial effects of genetic variation at a number of different genes and their interaction with relevant environmental exposures. The goal of this book is to introduce gene prioritization aspects and the candidate gene prioritization algorithms to give readers a comprehensive view on the subject

In the past century, nearly all of the biological sciences have been directly affected by discoveries and developments in genetics, a fast-evolving subject with important theoretical dimensions. In this rich and accessible book, Paul Griffiths and Karola Stotz show how the concept of the gene has evolved and diversified across the many fields that make up modern biology. By examining the molecular biology of the'environment', they situate genetics in the developmental biology of whole organisms, and reveal how the molecular biosciences have undermined the nature/nurture distinction. Their discussion gives full weight to the revolutionary impacts of molecular biology, while rejecting'genocentrism'and'reductionism', and brings the topic right up to date with the philosophical implications of the most recent developments in genetics. Their book will be invaluable for those studying the philosophy of biology, genetics and other life sciences.

Obesity and diabetes develop as a complex result of genetic, metabolic and environmental factors and are characterized by increased lipogenesis and lipid accumulation in many tissues. Stearoyl-CoA desaturase (SCD) genes are a critical regulator of lipogenesis and catalyzes the synthesis of monounsaturated fatty acids (MUFA), mainly oleoyl- (18:1n9) and palmitoleoyl-CoA (16:1n7). These MUFAs are the major fatty acid substrates for the synthesis of triglycerides, cholesterol esters, wax esters and membrane phospholipids. There are 4 SCD isoforms (SCD1-4) in mice and two (hSCD1 and hSCD5) expressed in humans. At first glance, stearoyl-CoA desaturase enzyme would be considered a housekeeping enzyme because it synthesizes oleate a well-known fatty acid that is abundant in many dietary sources. However numerous studies have shown that SCD is a very highly regulated enzyme that features in so many physiological processes ranging from fat differentiation, carbohydrate and fat metabolism, inflammation and cancer. The editor's studies using stearoyl-CoA desaturase knockout (SCD1-/-) mice and studies of other investigators using pharmacological approaches to reduce SCD1 expression in mouse tissues have all established that the expression of SCD1 gene isoform represents a key step in partitioning of lipids between storage and oxidation. High SCD expression favors fat storage leading to obesity while reduced SCD expression favors fat burning and leanness. Although these studies clearly illustrated that SCD1 expression is involved in the development of obesity and insulin resistance, questions remain in the elucidation of the mechanisms involved and role of SCD1. This book includes chapters by leading researchers on SCD Genes in the brain, heart, muscle, liver metabolism, Colitis, and more. ​

This title includes a number of Open Access chapters.Epigenetics refers to DNA and chromatin modifications that play an important role in the regulation of various genomic functions. This important book reviews human and cellular data that underline paradoxical findings with respect to the contribution of heredity and environment to phenotype. The

Chapter 1 - Gear Chapter 2 - Bevel Gear Chapter 3 - Spiral Bevel Gear and Herringbone Gear Chapter 4 - Worm Drive Chapter 5 - Epicyclic Gearing Chapter 6 - Harmonic Drive and Non–Circular Gear Chapter 7 - Backlash (Engineering) Chapter 8 - Derailleur Gears Chapter 9 - Hub Gear Chapter 10 - Belt (Mechanical) Chapter 11 - Conveyor Belt Chapter 12 - Timing Belt Chapter 13 - Pulley Chapter 14 - Line Shaft Chapter 15 - Clutch Chapter 16 - Electromagnetic Clutch Chapter 17 - Friction–Plate Electromagnetic Clutch

Now available in paperback, Molecular Plant Breeding provides an integrative overview of issues from basic theories to their applications to crop improvement. Chapters include discussions of breeding methodology, quantitative genetics, genomics and bioinformatics and present statistical issues related to gene mapping, marker-assisted selection and genotype by environment interactions in clear and concise language. Providing an integrated profile of molecular breeding in plants, this book will be an essential resource for researchers and students involved in plant biology and breeding, genetics and applied genomics.

As research progresses and information continues to proliferate in the field of molecular design for therapeutic use, there is a need for a reference that brings current theory and proven practice together in a how-to volume. This reference guides scientists new to the field on how to design small molecules that interact with critical protein targets. The chapters condense useful material into a manageable format which is carefully organized and presented. It offers an essential resource for a variety of chemists in academia, and the biotech and pharmaceutical industries, as well as professionals in complementary fields.

Against a backdrop of the history of the gene as a scientific and a cultural icon, How the Gene Got Its Groove examines how'genes'function as rhetorical objects. Returning to Wilhelm Johannsen's original argument for the term, Elizabeth Parthenia Shea maintains that the gene was, first and foremost, a rhetorical invention, designed to lay claim to a material reality and to dissociate itself from the problems of language, conjecture, and rhetorical uncertainty. She traces the rhetorical work of the gene through scientific and nonscientific arguments throughout the twentieth century. The gene's travels between scientific and popular texts challenge us to recognize the subtle powers of figurative language in creating a sense that matters of science stand outside the contingencies of language and the influences of rhetoric.

What exactly is a gene? How does cloning actually work? Are designerbabies a bad idea? Could we ever clone a human? The Rough Guide ToGenes & Cloning answers all these questions and more. From theinside story of cells and their structure and the sleuths who crackedthe genetic code to DNA cloning, twins and Dolly the sheep. Illustratedthroughout with helpful pictures and diagrams, this Rough Guide turnsthe microscope on the things that make us what we are.

“… an excellent book… achieves all of its goals with style, clarity and completeness… You can see the power and possibilities of molecular genetics as you read…” –Human Genetics'This volume hits an outstanding balance among readability, coverage, and detail.'–Biochemistry and Molecular Biology Education Rapid advances in a collection of techniques referred to as gene technology, genetic engineering, recombinant DNA technology and gene cloning have pushed molecular biology to the forefront of the biological sciences. This new edition of a concise, well-written textbook introduces key techniques and concepts involved in cloning genes and in studying their expression and variation. The book opens with a brief review of the basic concepts of molecular biology, before moving on to describe the key molecular methods and how they fit together. This ranges from the cloning and study of individual genes to the sequencing of whole genomes, and the analysis of genome-wide information. Finally, the book moves on to consider some of the applications of these techniques, in biotechnology, medicine and agriculture, as well as in research that is causing the current explosion of knowledge across the biological sciences. From Genes to Genomes: Concepts and Applications of DNA Technology, Second Edition includes full two-colour design throughout. Specific changes for the new edition include: Strengthening of gene to genome theme Updating and reinforcing of material on proteomics, gene therapy and stem cells More eukaryotic/mammalian examples and less focus on bacteria This textbook is must-have for all undergraduates studying intermediate molecular genetics within the biological and biomedical sciences. It is also of interest for researchers and all those needing to update their knowledge of this rapidly moving field.

In The Poetics of DNA, Judith Roof examines the rise of this powerful symbol and the implications of its ascendancy for the ways we thinkabout ourselves, about one another, and about the universe. A hyperbolized notion of DNA has become a vector, Roof argues, through which older ways of thinking can merge with the new, advancing long-discredited and insidious ideas.

This book reflects the ideas of a Spring school held March 2005 in Wageningen.

Tools developed by statistical physicists are of increasing importance in the analysis of complex biological systems. Physics in Molecular Biology, first published in 2005, discusses how physics can be used in modeling life. It begins by summarizing important biological concepts, emphasizing how they differ from the systems normally studied in physics. A variety of topics, ranging from the properties of single molecules to the dynamics of macro-evolution, are studied in terms of simple mathematical models. The main focus of the book is on genes and proteins and how they build systems that compute and respond. The discussion develops from simple to complex systems, and from small-scale to large-scale phenomena. This book will inspire advanced undergraduates and graduate students in physics to approach biological subjects from a physicist's point of view. It is self-contained, requiring no background knowledge of biology, and only familiarity with basic concepts from physics, such as forces, energy, and entropy.

'The DNA Mystique is a wake-up call to all who would dismiss America's love affair with'the gene'as a merely eccentric obsession.'--In These Times'Nelkin and Lindee are to be warmly congratulated for opening up this intriguing field [of genetics in popular culture] to further study.'--Nature The DNA Mystique suggests that the gene in popular culture draws on scientific ideas but is not constrained by the technical definition of the gene as a section of DNA that codes for a protein. In highlighting DNA as it appears in soap operas, comic books, advertising, and other expressions of mass culture, the authors propose that these domains provide critical insights into science itself. With a new introduction and conclusion, this edition will continue to be an engaging, accessible, and provocative text for the sociology, anthropology, and bioethics classroom, as well as stimulating reading for those generally interested in science and culture.

In this book a distinguished scientist-historian offers a critical account of how biochemistry and molecular biology emerged as major scientific disciplines from the interplay of chemical and biological ideas and practice. Joseph S. Fruton traces the historical development of these disciplines from antiquity to the present time, examines their institutional settings, and discusses their impact on medical, pharmaceutical, and agricultural practice.