Sex Chromosomes
DOWNLOAD
Download Sex Chromosomes PDF/ePub or read online books in Mobi eBooks. Click Download or Read Online button to get Sex Chromosomes book now. This website allows unlimited access to, at the time of writing, more than 1.5 million titles, including hundreds of thousands of titles in various foreign languages. If the content not found or just blank you must refresh this page
Sex Chromosomes And Sex Linked Genes
DOWNLOAD
Author : Susumu Ohno
language : en
Publisher: Springer Science & Business Media
Release Date : 2013-06-29
Sex Chromosomes And Sex Linked Genes written by Susumu Ohno and has been published by Springer Science & Business Media this book supported file pdf, txt, epub, kindle and other format this book has been release on 2013-06-29 with Science categories.
Natural selection operates among individual organisms which differ in their genetic constitution. The degree of hereditary variability within a species is greatly enhanced by cross-fertilization. Indeed, the mechanism of sexual reproduction occurred very early in evolution, for it is seen today even in bacteria. In Escherichia coli, fertilization occurs by passage of the single chromosome from the male into the female bacterium (LEDERBERG, 1959). In multicellular organisms, the separation of germ from soma, and the production of haploid gametes became mandatory. The gametes were of two types. One, extremely mobile, was designed to seek out and penetrate the other, which loaded with nutrients, received the mobile gamete and intiated the development of a new individual. The foundation for true bisexuality was thus laid. In the primitive state of bisexuality, whether an individual is to be a sperm-producing male or an egg-producing female appears to be decided rather haphazardly. In the worm, Banelia viridis, the minute males are parasites in the female. Larvae that become attached to the proboscis of an adult female become males, while unattached larvae sink to the bottom and become females (BALTZER, 1935). The more sophisticated state of bisexuality was initiated by setting aside a particular pair of chromosomes for specialization and making either the male or the female a heterogametic sex. Sex chromosomes as we know them were thus born.
Sex Chromosomes
DOWNLOAD
Author : Ursula Mittwoch
language : en
Publisher: Academic Press
Release Date : 2014-06-28
Sex Chromosomes written by Ursula Mittwoch and has been published by Academic Press this book supported file pdf, txt, epub, kindle and other format this book has been release on 2014-06-28 with Science categories.
Sex Chromosomes focuses on the study of sex chromosomes, including human chromosomal abnormalities, behavior and characteristics of chromosomes, and cell division. The book first offers information on the chromosomal basis of sex determination, as well as development of the cell theory, mitosis, fertilization, meiosis, and discovery of sex chromosomes. The publication also ponders on the mitosis, meiosis, and formation of gametes. Discussions focus on the special characteristics of sex chromosomes, abnormalities of cell division, and sexual differentiation. The manuscript reviews sex chromosomes in plants, Drosophila, and Lepidoptera. The book also examines sex-chromosome mechanisms that differ the classic type; sex chromosomes in fishes, amphibia, reptiles, and birds; and sex chromosomes in man. Discussions focus on normal human sex chromosomes, Turner's syndrome, Klinefelter's syndrome, true hermaphrodites, testicular feminization, and pseudohermaphrodites. Sex chromosomes in mammals other than man, including monotremata, marsupialia, insectivora, rodentia, and carnivora, are discussed. The publication is a dependable reference for readers interested in the study of sex chromosomes.
The Evolution Of Sex Determination
DOWNLOAD
Author : Leo W. Beukeboom
language : en
Publisher:
Release Date : 2014
The Evolution Of Sex Determination written by Leo W. Beukeboom and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2014 with Medical categories.
Sexual reproduction is a fundamental aspect of life. It is defined by the occurrence of meiosis and the fusion of two gametes of different sexes or mating types. Sex-determination mechanisms are responsible for the sexual fate and development of sexual characteristics in an organism, be it a unicellular alga, a plant, or an animal. In many cases, sex determination is genetic: males and females have different alleles or different genes that specify their sexual morphology. In animals, this is often accompanied by chromosomal differences. In other cases, sex may be determined by environmental (e.g. temperature) or social variables (e.g. the size of an organism relative to other members of its population). Surprisingly, sex-determination mechanisms are not evolutionarily conserved but are bewilderingly diverse and appear to have had rapid turnover rates during evolution. Evolutionary biologists continue to seek a solution to this conundrum. What drives the surprising dynamics of such a fundamental process that always leads to the same outcome: two sex types, male and female? The answer is complex but the ongoing genomic revolution has already greatly increased our knowledge of sex-determination systems and sex chromosomes in recent years. This novel book presents and synthesizes our current understanding, and clearly shows that sex-determination evolution will remain a dynamic field of future research. The Evolution of Sex Determination is an advanced, research level text suitable for graduate students and researchers in genetics, developmental biology, and evolution.
Sex Chromosomes
DOWNLOAD
Author : Cynthia N. Weingarten
language : en
Publisher: Nova Science Publishers
Release Date : 2009
Sex Chromosomes written by Cynthia N. Weingarten and has been published by Nova Science Publishers this book supported file pdf, txt, epub, kindle and other format this book has been release on 2009 with Sex chromosome abnormalities categories.
Sex chromosomes determine the sex of an organism. A human somatic cell has two sex chromosomes: XY in male and XX in female. A human germ cell has one sex chromosome: X or Y in a sperm and X in an egg. When an X-sperm is combined with an egg, the resulting zygote (fertilised egg) will contain two X chromosomes. A person developed from the XX-zygote will have the characteristics of a female. Combination of a Y-sperm and an egg will produce a male. Usually, a woman has two X chromosomes (XX) and a man one X and one Y (XY). However, both male and female characteristics can sometimes be found in one individual, and it is possible to have XY women and XX men. Analysis of such individuals has revealed some of the molecules involved in sex determination, including one called SRY, which is important for testis formation. SRY (which stands for sex-determining region Y gene) is found on the Y chromosome. In the cell, it binds to other DNA and in doing so distorts it dramatically out of shape. This alters the properties of the DNA and likely alters the expression of a number of genes, leading to testis formation. Most XX men who lack a Y chromosome do still have a copy of the SRY gene on one of their X chromosomes (moved there by chromosomal translocation). This copy accounts for their maleness. However, because the remainder of the Y chromosome is missing they frequently do not develop secondary sexual characteristics in the usual way. This book presents the latest research in the field from around the world.
The 7 Sexes
DOWNLOAD
Author : Elof Axel Carlson
language : en
Publisher: Indiana University Press
Release Date : 2013-02-12
The 7 Sexes written by Elof Axel Carlson and has been published by Indiana University Press this book supported file pdf, txt, epub, kindle and other format this book has been release on 2013-02-12 with Psychology categories.
Few of us know much about the biology of sex determination, but what could be more interesting than to discover how we are shaped into males and females? In this book, Elof Carlson tells the incredible story of the difficult quest to understand how the body forms girls and boys. Carlson's history takes us from antiquity to the present day to detail how each component of human reproduction and sexuality was identified and studied, how this knowledge enlarged our understanding of sex determination, and how it was employed to interpret such little understood aspects of human biology as the origin of intersex births.
Sex Itself
DOWNLOAD
Author : Sarah S. Richardson
language : en
Publisher: University of Chicago Press
Release Date : 2013-12-13
Sex Itself written by Sarah S. Richardson and has been published by University of Chicago Press this book supported file pdf, txt, epub, kindle and other format this book has been release on 2013-12-13 with Science categories.
Human genomes are 99.9 percent identical—with one prominent exception. Instead of a matching pair of X chromosomes, men carry a single X, coupled with a tiny chromosome called the Y. Tracking the emergence of a new and distinctive way of thinking about sex represented by the unalterable, simple, and visually compelling binary of the X and Y chromosomes, Sex Itself examines the interaction between cultural gender norms and genetic theories of sex from the beginning of the twentieth century to the present, postgenomic age. Using methods from history, philosophy, and gender studies of science, Sarah S. Richardson uncovers how gender has helped to shape the research practices, questions asked, theories and models, and descriptive language used in sex chromosome research. From the earliest theories of chromosomal sex determination, to the mid-century hypothesis of the aggressive XYY supermale, to the debate about Y chromosome degeneration, to the recent claim that male and female genomes are more different than those of humans and chimpanzees, Richardson shows how cultural gender conceptions influence the genetic science of sex. Richardson shows how sexual science of the past continues to resonate, in ways both subtle and explicit, in contemporary research on the genetics of sex and gender. With the completion of the Human Genome Project, genes and chromosomes are moving to the center of the biology of sex. Sex Itself offers a compelling argument for the importance of ongoing critical dialogue on how cultural conceptions of gender operate within the science of sex.
Sex Chromosomes
DOWNLOAD
Author : Franz Schrader
language : en
Publisher:
Release Date : 1928
Sex Chromosomes written by Franz Schrader and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 1928 with Chromosomes categories.
Sex Chromosomes And Sex Determination In Vertebrates
DOWNLOAD
Author : Alberto J. Solari
language : en
Publisher: CRC Press
Release Date : 1993-10-22
Sex Chromosomes And Sex Determination In Vertebrates written by Alberto J. Solari and has been published by CRC Press this book supported file pdf, txt, epub, kindle and other format this book has been release on 1993-10-22 with Nature categories.
The cloning of the SRY gene and the attainment of XX mice transgenic for the Sry gene opened a new era in research on sex determination. This book surveys current knowledge of sex chromosomes and sex determination in all vertebrate classes, relying on the restriction of genetic recombination in sex chromosomes as the unifying concept of this subject. The book's interdisciplinary approach integrates contributions from the fields of cytogenetics, molecular biology, developmental biology, and evolutionary genetics. A detailed treatment of the meiotic behavior of sex chromosomes is featured, and the entire text is supplemented by numerous schemes, drawings, and electron micrographs. The book will be valuable to general cytogeneticists, vertebrate zoologists, and veterinarian and medical practitioners interested in the foundations of sex determination and the current knowledge of sex chromosomes. It will also interest students in advanced undergraduate and graduate courses in these areas.
Sex Chromosomes Advances In Research And Application 2011 Edition
DOWNLOAD
Author :
language : en
Publisher: ScholarlyEditions
Release Date : 2012-01-09
Sex Chromosomes Advances In Research And Application 2011 Edition written by and has been published by ScholarlyEditions this book supported file pdf, txt, epub, kindle and other format this book has been release on 2012-01-09 with Medical categories.
Sex Chromosomes: Advances in Research and Application: 2011 Edition is a ScholarlyBrief™ that delivers timely, authoritative, comprehensive, and specialized information about Sex Chromosomes in a concise format. The editors have built Sex Chromosomes: Advances in Research and Application: 2011 Edition on the vast information databases of ScholarlyNews.™ You can expect the information about Sex Chromosomes in this eBook to be deeper than what you can access anywhere else, as well as consistently reliable, authoritative, informed, and relevant. The content of Sex Chromosomes: Advances in Research and Application: 2011 Edition has been produced by the world’s leading scientists, engineers, analysts, research institutions, and companies. All of the content is from peer-reviewed sources, and all of it is written, assembled, and edited by the editors at ScholarlyEditions™ and available exclusively from us. You now have a source you can cite with authority, confidence, and credibility. More information is available at http://www.ScholarlyEditions.com/.
Sex Chromosomes And Sex Determining Genes
DOWNLOAD
Author : Ken Reed
language : en
Publisher:
Release Date : 1993
Sex Chromosomes And Sex Determining Genes written by Ken Reed and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 1993 with Mammals categories.