Download or read book Reproduction and Development in Minor Phyla written by T. J. Pandian and published by CRC Press. This book was released on 2021-05-14 with total page 302 pages. Available in PDF, EPUB and Kindle. Book excerpt: The 26 recognized minor phyla comprise aberrant clades, as most of them terminate as blind offshoots. Untied from the discussion on their phylogenesis of minor phyla, this book is largely devoted, for the first time, to aspects of reproduction and development in minor phyletics. The minor phyla are not as speciose (1,795 species/phylum) as the major phyla (157,066 species/phylum) are. The accumulation of deleterious genes causes inbreeding depression among progenies arising from parthenogenesis, clonal multiplication and selfing hermaphrodites. The reason for the limited species diversity in minor phyla is traced to (i) eutelism in 65.7% of minor phyletics and (ii) existence of 21.6% clonals, (iii) 6.4% parthenogens and (iv) 1.2% selfing hermaphroditism. Gonochorism obligately requires motility to search for a mate. The combination of low motility and gonochorism from Placozoa to hemocoelomatic minor phyla has limited diversity to
Download or read book Reproduction and Development in Minor Phyla written by T. J. Pandian and published by CRC Press. This book was released on 2021-05-14 with total page 333 pages. Available in PDF, EPUB and Kindle. Book excerpt: The 26 recognized minor phyla comprise aberrant clades, as most of them terminate as blind offshoots. Untied from the discussion on their phylogenesis of minor phyla, this book is largely devoted, for the first time, to aspects of reproduction and development in minor phyletics. The minor phyla are not as speciose (1,795 species/phylum) as the major phyla (157,066 species/phylum) are. The accumulation of deleterious genes causes inbreeding depression among progenies arising from parthenogenesis, clonal multiplication and selfing hermaphrodites. The reason for the limited species diversity in minor phyla is traced to (i) eutelism in 65.7% of minor phyletics and (ii) existence of 21.6% clonals, (iii) 6.4% parthenogens and (iv) 1.2% selfing hermaphroditism. Gonochorism obligately requires motility to search for a mate. The combination of low motility and gonochorism from Placozoa to hemocoelomatic minor phyla has limited diversity to
Download or read book Reproduction and Development in Platyhelminthes written by T J Pandian and published by CRC Press. This book was released on 2021-09-30 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a comprehensive synthesis of all aspects of Reproduction and Development in Platyhelminths covering from Acoela in Turbellaria to Taenioidea in Cestoda. It elaborates the life cycle and characteristics of different platyhelminthic taxa.
Download or read book Reproduction and Development in Crustacea written by T. J. Pandian and published by CRC Press. This book was released on 2016-04-05 with total page 295 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dating back to the early Cambrian period, crustaceans had ample time to undertake endless experimentation with form and function. Today, no other group of plants or animals on the planet exhibit the range of morphological diversity seen among extant Crustacea. With more than 52,000 species, they are placed fourth in terms of overall species diversi
Download or read book Evolution and Speciation in Animals written by T. J. Pandian and published by CRC Press. This book was released on 2021-09-23 with total page 346 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book represents the first attempt to quantify environmental factors and life history traits that accelerate or decelerate species diversity in animals. About 15%, 8% and 77% of species are distributed in marine (70% of earth’s surface), freshwater (terra firma fosters more diversity. The harsh hadal, desert and elevated montane habitats restrict diversity to 0.5-4.2%. Costing more time and energy, osmotrophic and suspension modes of food acquisition limit diversity to Selfing hermaphrodites (0.9%), parthenogens ( Incidence of heterogamety is four-times more in males than in females. Hence, evolution is more a male-driven process. Egg size is determined by environmental factors, but lecithality is genetically fixed. In poikilotherms, sex is also determined by gene(s), but differentiation by environmental factors. The extra-ovarian vitellogenesis (> 96%), spermatozoan (81%) rather than spermatophore mechanism of sperm transfer, promiscuity and polygamy over monogamy, iteroparity (99.6%) over semelparity and internal fertilization (84%) are preferred, as they accelerate diversity. Body size and egg size determine fecundity. Indirect life cycle (82%) and incorporation of feeding larval stages accelerate diversity. Brooding and viviparity (6.4%) decelerate it. Parasitism extends life span and liberates fecundity from eutelism. Evolution is an ongoing process, and speciation and extinction are its unavoidable by-products. The in-built conservation mechanism of reviving life after a sleeping duration has been reduced from a few million years in microbial spores to a few thousand years in plant seeds and a few hundred years in dormant eggs in animals. Hence, animal conservation requires priority. The existence of temperature-resistant/insensitive individuals, strains and species shall flourish during the ongoing global warming and earth shall continue with such burgeoning species, hopefully inclusive of man.
Download or read book Evolution and Speciation in Fungi and Eukaryotic Biodiversity written by T. J. Pandian and published by CRC Press. This book was released on 2023-10-13 with total page 349 pages. Available in PDF, EPUB and Kindle. Book excerpt: Being sessiles like autotrophic plants and heterotrophics as animals, fungi are fascinating eukaryotes. In them, the need for external digestion has demanded surface expansion and limited tissues to 2/y. The mycorrhizas facilitate 85% angiosperms to acquire water and minerals, enhance productivity and fight against drought and pollutants. During the geological past, lichens have weathered rock and formed the present landscape. Only 121 fungal species excrete digestive enzymes to meet industrial demand. The beneficial fungi contribute 1,000 billion US$. Parasitic fungi cause 1.6 million human deaths and > 20% loss of commercial crops. Despite their ecological and economic importance, no university offers a degree course in Mycology. For 2,056,907 eukaryotic species, this book elaborates the role played by environmental factors (i) spatial distribution, (ii) light-temperature, (iii) precipitation-liquid water and biological attributes, (iv) cellularity, (v) symmetry, (vi) clonality, (vii) sexuality, (viii) modality and (ix) motility that either accelerate or decelerate biodiversity. About 20 and 80% eukaryotes are aquatics and terrestrials. Decreasing light intensity and temperature reduce diversity from the equator toward the polar zones. Water availability also reduces the diversity from 5.4 - 65.5 species/km2 in tropical evergreen forests to 2 in deserts and polar zones. Unicellularity and radial symmetry decelerate the diversity to 200 in mammals reduce clonality from 100 to 0%. Strategies developed by eukaryotes reduce selfing by
Download or read book The Biology of Reproduction written by Giuseppe Fusco and published by Cambridge University Press. This book was released on 2019-10-10 with total page 491 pages. Available in PDF, EPUB and Kindle. Book excerpt: A look into the phenomena of sex and reproduction in all organisms, taking an innovative, unified and comprehensive approach.
Download or read book Modern Text Book of Zoology Invertebrates written by Prof. R.L.Kotpal and published by Rastogi Publications. This book was released on 2012 with total page 908 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Animal Kingdom A Very Short Introduction written by Peter Holland and published by OUP Oxford. This book was released on 2011-11-24 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt: The animal world is immensely diverse, and our understanding of it has been greatly enhanced by analysis of DNA and the study of evolution and development ('evo-devo'). In this Very Short Introduction Peter Holland presents a modern tour of the animal kingdom. Beginning with the definition of animals (not obvious in biological terms), he takes the reader through the high-level groupings of animals (phyla) and new views on their evolutionary relationships based on molecular data, together with an overview of the biology of each group of animals. The phylogenetic view is central to zoology today and the volume will be of great value to all students of the life sciences, as well as providing a concise summary for the interested general reader. ABOUT THE SERIES: The Very Short Introductions series from Oxford University Press contains hundreds of titles in almost every subject area. These pocket-sized books are the perfect way to get ahead in a new subject quickly. Our expert authors combine facts, analysis, perspective, new ideas, and enthusiasm to make interesting and challenging topics highly readable.
Download or read book Reproduction Genetics and Distributions of Marine Organisms written by John Stanley Ryland and published by Olsen & Olsen. This book was released on 1989 with total page 488 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Invertebrate Embryology and Reproduction written by Fatma El-Bawab and published by Academic Press. This book was released on 2020-01-18 with total page 934 pages. Available in PDF, EPUB and Kindle. Book excerpt: Invertebrate Embryology and Reproduction deals with the practical and theoretical objectives of the descriptive embryology of invertebrates, along with discussions on reproduction in these groups of animals. It explains several morphological and anatomical expressions in the field and covers the embryology of invertebrate animals, starting from the Protozoa, to the Echinodermata, the Protochordate and Tunicates. These groups include economically important aquatic invertebrates, such as crustaceans, as well as medically important invertebrates and economic arthropods. Each chapter is preceded by the taxonomy of the discussed phylum and/or the species to enable the reader to locate the systematic position. Covers phylum definition, general characteristics, classification, reproduction, agametic reproduction, gametic reproduction, spawning, fertilization, development and embryogenesis Includes recent findings in the area, along with detailed figures and photos that illustrate important concepts Brings together difficult-to-obtain research data from the field, not only in Egyptian libraries, but globally, and previously only found through specialized references not widely available Clarifies descriptions with striking photos and electron microscopical studies of different species
Download or read book Zoology for Degree Students B Sc First Year written by Agarwal V.K. and published by S. Chand Publishing. This book was released on 2011 with total page 1516 pages. Available in PDF, EPUB and Kindle. Book excerpt: Unit I : Animal Diversity-I ( Non Chordate :Lower & Higher) Part A : Lower Non-Chordates (Invertebrates) Part B: Higher Non-Chordate Unit-Ii : Cell Biology & Biochemistry Unit-Iii : Genetics
Download or read book Encyclopedia of Reproduction written by and published by Academic Press. This book was released on 2018-06-29 with total page 3905 pages. Available in PDF, EPUB and Kindle. Book excerpt: Encyclopedia of Reproduction, Second Edition, Six Volume Set comprehensively reviews biology and abnormalities, also covering the most common diseases in humans, such as prostate and breast cancer, as well as normal developmental biology, including embryogenesis, gestation, birth and puberty. Each article provides a comprehensive overview of the selected topic to inform a broad spectrum of readers, from advanced undergraduate students, to research professionals. Chapters also explore the latest advances in cloning, stem cells, endocrinology, clinical reproductive medicine and genomics. As reproductive health is a fundamental component of an individual’s overall health status and a central determinant of quality of life, this book provides the most extensive and authoritative reference within the field. Provides a one-stop shop for information on reproduction that is not available elsewhere Includes extensive coverage of the full range of topics, from basic, to clinical considerations, including evolutionary advances in molecular, cellular, developmental and clinical sciences Includes multimedia and interactive teaching tools, such as downloadable PowerPoint slides, video content and interactive elements, such as the Virtual Microscope
Download or read book Developmental Biology written by M.A. SUBRAMANIAN and published by MJP Publisher. This book was released on 2019-06-20 with total page 246 pages. Available in PDF, EPUB and Kindle. Book excerpt: 1. INTRODUTION, 2. HISTORICAL REVIEW AND THEORIES OF DEVELOPMENTAL BIOLOGY, 3. GAMETOGENESIS, 4. ORGANIZATION OF EGG—POLARITY, SYMMETRY AND GRADIENTS, 5. OVULATION AND EGG TRANSPORT, 6. FERTILIZATION, 7. EGG CORTEX AND DEVELOPMENT—CORTICAL REACTIONS AND THEORIES OF FERTILIZATION, 8. PARTHENOGENESIS—VIRGIN BIRTH, 9. CLEAVAGE, 10. FATE MAPS AND CELL LINEAGE—PRESUMPTIVE AREAS AND THEIR SIGNIFICANCE, 11. MORPHOGENETIC MOVEMENTS AND GASTRULATION, 12. CELL DIFFERENTIATION, 13. GERM LAYERS AND ORGANOGENESIS, 14. INDUCTION (ORGANIZER CONCEPT), 15. FOETAL MEMBRANES OR EXTRA-EMBRYONIC MEMBRANES IN AMNIOTES (CHICK AND PIG), 16. IMPLANTATION AND PLACENTATION IN MAMMALS (EUTHERIAN MAMMALS), 17. TERATOLOGY, 18. PRENATAL DIAGNOSIS OF ABNORMALITIES, 19. METAMORPHOSIS, 20. REGENERATION, 21. REPRODUTIVE AND DEVELOPMENTAL PATTERNS IN INVERTEBRATES, 22. INVERTEBRATE LARVAE AND THEIR SIGNIFICANCE.
Download or read book Protozoa Porifera Coelenterata Helminthes Annelida Arthropoda Mollusca Echinodermata Minor phyla written by G.S Sandhu and published by . This book was released on 2005 with total page 508 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Perspectives in Animal Phylogeny and Evolution written by Alessandro Minelli and published by Oxford University Press. This book was released on 2009 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt: Animal phylogeny is undergoing a major revolution due to the availability of an ever increasing amount of molecular data, the application of novel methods of phylogenetic reconstruction, and advances in palaeontology and molecular developmental biology.This book revises the major events in animal evolution in the light of these recent advances.
Download or read book Zoology for Degree Students For B Sc Hons 1st Semester As per CBCS written by Agarwal V.K. and published by S. Chand Publishing. This book was released on with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This textbook has been designed to meet the needs of B.Sc. (Hons.) First Semester students of Zoology as per the UGC Choice Based Credit System (CBCS). Comprehensively written, it explains the essential principles, processes and methodology of Acoelomate Non-Chordates along with Protista, and Ecology. This textbook is profusely illustrated with well-drawn labelled diagrams, not only to supplement the descriptions, but also for sound understanding of the concepts.
