Germ Line — Soma Differentiation

Germ Line — Soma Differentiation PDF Author: W. Hennig
Publisher: Springer Science & Business Media
ISBN: 3540398384
Category : Science
Languages : en
Pages : 206

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Book Description
One of the oldest problems in developmental biology is the differentiation between germ line and somatic cells. The continuity of germ line cells between subsequent generations of multicellular organisms was first suggested by Owen, and later elaborated by A. Weismann to his famous germ line theory. His additional assumption that cellular differentiation was based on a differential representation of the genetic material in somatic cells was soon disproved. In some, apparently exceptional, cases, however, such differences in the genetic material between germ line and somatic cells were discovered. The best-known example is the nematod Ascaris. Boveri discovered and studied the fundamental differences in the karyotypes of germ line and soma of Parascaris equorum. Later, similar situations were found in some other organisms. However, in particular the work ofSpemann demonstrated that cellular differentiation in general is not accompanied by fundamental changes of the genetic material. Subsequently, the relatively few examples of germ line-soma differences achieved by chromatin elimination processes have been considered as a curiosity. Experimental studies have been essentially restricted to Ascaris species and to the pioneering cytological studies of chromatin elimination by S. Beermann. Despite the large proportions of the genome involved in chromatin elimina tion, our knowledge of this process is still very restricted. In particular the biological meaning of this differentiation process is entirely obscure. In this context one must, however, consider that also for the majority of DNA sequences in eukaryotic genomes the biological relevance is unclear.

Germ Line — Soma Differentiation

Germ Line — Soma Differentiation PDF Author: W. Hennig
Publisher: Springer Science & Business Media
ISBN: 3540398384
Category : Science
Languages : en
Pages : 206

Get Book Here

Book Description
One of the oldest problems in developmental biology is the differentiation between germ line and somatic cells. The continuity of germ line cells between subsequent generations of multicellular organisms was first suggested by Owen, and later elaborated by A. Weismann to his famous germ line theory. His additional assumption that cellular differentiation was based on a differential representation of the genetic material in somatic cells was soon disproved. In some, apparently exceptional, cases, however, such differences in the genetic material between germ line and somatic cells were discovered. The best-known example is the nematod Ascaris. Boveri discovered and studied the fundamental differences in the karyotypes of germ line and soma of Parascaris equorum. Later, similar situations were found in some other organisms. However, in particular the work ofSpemann demonstrated that cellular differentiation in general is not accompanied by fundamental changes of the genetic material. Subsequently, the relatively few examples of germ line-soma differences achieved by chromatin elimination processes have been considered as a curiosity. Experimental studies have been essentially restricted to Ascaris species and to the pioneering cytological studies of chromatin elimination by S. Beermann. Despite the large proportions of the genome involved in chromatin elimina tion, our knowledge of this process is still very restricted. In particular the biological meaning of this differentiation process is entirely obscure. In this context one must, however, consider that also for the majority of DNA sequences in eukaryotic genomes the biological relevance is unclear.

Germline Stem Cells

Germline Stem Cells PDF Author: Steven X. Hou
Publisher: Humana Press
ISBN: 9781617378805
Category : Science
Languages : en
Pages : 0

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Book Description
In this comprehensive and cutting-edge book, leading experts explore the parameters that define germline stem cells and the mechanisms that regulate the cell behavior in order to better isolate, characterize and maintain them. The volume begins by providing protocols for germline stem cell identification and regulation in model organisms, and concludes with detailed chapters covering current techniques involving in vitro culture and the applications of the cells.

Volvox

Volvox PDF Author: David L. Kirk
Publisher: Cambridge University Press
ISBN: 9780521452076
Category : Science
Languages : en
Pages : 210

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Book Description
This book reviews Volvox development and biology and, through this study, sheds light on the origins of multicellularity.

The Germ-plasm

The Germ-plasm PDF Author: August Weismann
Publisher:
ISBN:
Category : Heredity
Languages : en
Pages : 512

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Book Description


Germline Stem Cells

Germline Stem Cells PDF Author: Michael Buszczak
Publisher: Humana
ISBN: 9781493940158
Category : Science
Languages : en
Pages : 0

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Book Description
This second edition provides updated and new chapters on selected genetic, molecular, biochemical, and cell biological techniques. Chapter’s guide readers through methods and principles on primordial germ cells and germline stem cells, however many of these principles can be applied to different types of adult stem cells. Written in the highly successful Methods in Molecular Biology series format, chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and tips on troubleshooting and avoiding known pitfalls. Authoritative and cutting-edge, Germline Stem Cells: Second Edition aims to present the new findings and techniques that have developed since the first edition.

Mechanisms of Life History Evolution

Mechanisms of Life History Evolution PDF Author: Thomas Flatt
Publisher: OUP Oxford
ISBN: 0191621021
Category : Science
Languages : en
Pages : 506

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Book Description
Life history theory seeks to explain the evolution of the major features of life cycles by analyzing the ecological factors that shape age-specific schedules of growth, reproduction, and survival and by investigating the trade-offs that constrain the evolution of these traits. Although life history theory has made enormous progress in explaining the diversity of life history strategies among species, it traditionally ignores the underlying proximate mechanisms. This novel book argues that many fundamental problems in life history evolution, including the nature of trade-offs, can only be fully resolved if we begin to integrate information on developmental, physiological, and genetic mechanisms into the classical life history framework. Each chapter is written by an established or up-and-coming leader in their respective field; they not only represent the state of the art but also offer fresh perspectives for future research. The text is divided into 7 sections that cover basic concepts (Part 1), the mechanisms that affect different parts of the life cycle (growth, development, and maturation; reproduction; and aging and somatic maintenance) (Parts 2-4), life history plasticity (Part 5), life history integration and trade-offs (Part 6), and concludes with a synthesis chapter written by a prominent leader in the field and an editorial postscript (Part 7).

Meiosis and Gametogenesis

Meiosis and Gametogenesis PDF Author:
Publisher: Academic Press
ISBN: 0080584608
Category : Science
Languages : en
Pages : 447

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Book Description
In spite of the fact that the process of meiosis is fundamental to inheritance, surprisingly little is understood about how it actually occurs. There has recently been a flurry of research activity in this area and this volume summarizes the advances coming from this work. All authors are recognized and respected research scientists at the forefront of research in meiosis. Of particular interest is the emphasis in this volume on meiosis in the context of gametogenesis in higher eukaryotic organisms, backed up by chapters on meiotic mechanisms in other model organisms. The focus is on modern molecular and cytological techniques and how these have elucidated fundamental mechanisms of meiosis. Authors provide easy access to the literature for those who want to pursue topics in greater depth, but reviews are comprehensive so that this book may become a standard reference.Key Features* Comprehensive reviews that, taken together, provide up-to-date coverage of a rapidly moving field* Features new and unpublished information* Integrates research in diverse organisms to present an overview of common threads in mechanisms of meiosis* Includes thoughtful consideration of areas for future investigation

Heritable Human Genome Editing

Heritable Human Genome Editing PDF Author: The Royal Society
Publisher: National Academies Press
ISBN: 0309671132
Category : Medical
Languages : en
Pages : 239

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Book Description
Heritable human genome editing - making changes to the genetic material of eggs, sperm, or any cells that lead to their development, including the cells of early embryos, and establishing a pregnancy - raises not only scientific and medical considerations but also a host of ethical, moral, and societal issues. Human embryos whose genomes have been edited should not be used to create a pregnancy until it is established that precise genomic changes can be made reliably and without introducing undesired changes - criteria that have not yet been met, says Heritable Human Genome Editing. From an international commission of the U.S. National Academy of Medicine, U.S. National Academy of Sciences, and the U.K.'s Royal Society, the report considers potential benefits, harms, and uncertainties associated with genome editing technologies and defines a translational pathway from rigorous preclinical research to initial clinical uses, should a country decide to permit such uses. The report specifies stringent preclinical and clinical requirements for establishing safety and efficacy, and for undertaking long-term monitoring of outcomes. Extensive national and international dialogue is needed before any country decides whether to permit clinical use of this technology, according to the report, which identifies essential elements of national and international scientific governance and oversight.

Pharmacoepigenetics

Pharmacoepigenetics PDF Author: Ramón Cacabelos
Publisher: Academic Press
ISBN: 0128139404
Category : Medical
Languages : en
Pages : 986

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Book Description
Pharmacoepigenetics provides a comprehensive volume on the role of epigenetics and epigenomics in drug discovery and development, providing a detailed, but accessible, view of the field, from basic principles, to applications in disease therapeutics. Leading international researchers from across academia, clinical settings and the pharmaceutical industry discuss the influence of epigenetics and epigenomics in human pathology, epigenetic biomarkers for disease prediction, diagnosis, and treatment, current epigenetic drugs, and the application of epigenetic procedures in drug development. Throughout the book, chapter authors offer a balanced and objective discussion of the future of pharmacoepigenetics and its crucial contribution to the growth of precision and personalized medicine. - Fully examines the influence of epigenetics and epigenomics in human pathology, epigenetic biomarkers for disease prediction, diagnosis, treatment, current epigenetic drugs and the application of epigenetic procedures in drug development - Features chapter contributions from leading international researchers in academia, clinical settings and the pharmaceutical industry - Instructs researchers, students and clinicians on how to better interpret and employ pharmacoepigenetics in drug development, efficiency and safety - Provides a balanced and objective discussion of the future of pharmacoepigenetics and its crucial role in precision medicine

The Biology of Hagfishes

The Biology of Hagfishes PDF Author: Jørgen Mørup Jørgensen
Publisher: Springer Science & Business Media
ISBN: 9401158347
Category : Science
Languages : en
Pages : 577

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Book Description
The hagfishes comprise a uniform group of some 60 species inhabiting the cool or deep parts of the oceans of both hemispheres. They are considered the most primitive representatives of the group of craniate chordates, which - apart from the hagfishes that show no traces of verte brae -includes all vertebrate animals. Consequently the hagfishes have played and still playa central role in discussions concerning the evolution of the vertebrates. Although most of the focus on hagfishes may be the result of their being primitive, it should not be forgotten that, at the same time, they are specialized animals with a unique way of life that is interesting in its own right. It is now more than 30 years since a comprehensive treatise on hagfishes was published. The Biology of Myxine, edited by Alf Brodal and Ragnar Fange (Universitetsforlaget, Oslo, 1963), provided a wealth of information on the biology of hagfishes, and over the years remained a major source of information and inspiration to students of hagfishes.