Sexual Reproduction In Animals And Plants

This book contains the proceedings of the International Symposium on the Mechanisms of Sexual Reproduction in Animals and Plants, where many plant and animal reproductive biologists gathered to discuss their recent progress in investigating the shared mechanisms and factors involved in sexual reproduction. This now is the first book that reviews recent progress in almost all fields of plant and animal fertilization. It was recently reported that the self-sterile mechanism of a hermaphroditic marine invertebrate (ascidian) is very similar to the self-incompatibility system in flowering plants. It was also found that a male factor expressed in the sperm cells of flowering plants is involved in gamete fusion not only of plants but also of animals and parasites. These discoveries have led to the consideration that the core mechanisms or factors involved in sexual reproduction may be shared by animals, plants and unicellular organisms. This valuable book is highly useful for reproductive biologists as well as for biological scientists outside this field in understanding the current progress of reproductive biology.

Reproduction is the biological process by which new individual organisms are produced. Reproduction is a fundamental feature of all known life; each individual organism exists as the result of reproduction. The known methods of reproduction are broadly grouped into two main types: sexual and asexual. In asexual reproduction, an individual can reproduce without involvement with another individual of that species. The division of a bacterial cell into two daughter cells is an example of asexual reproduction. Asexual reproduction is not, however, limited to single-celled organisms. Most plants have the ability to reproduce asexually. Sexual reproduction requires the involvement of two individuals, typically one of each sex. Normal human reproduction is a common example of sexual reproduction. Most animals and plants reproduce sexually. Sexually reproducing organisms have two sets of genes for every trait (called alleles). Offspring inherit one allele for each trait from each parent, thereby ensuring that offspring have a combination of the parents' genes. Having two copies of every gene, only one of which is expressed, allows deleterious alleles to be masked, an advantage believed to have led to the evolutionary development of diploidy. This book presents the latest research in the field from around the globe.

Concepts of Biology is designed for the single-semester introduction to biology course for non-science majors, which for many students is their only college-level science course. As such, this course represents an important opportunity for students to develop the necessary knowledge, tools, and skills to make informed decisions as they continue with their lives. Rather than being mired down with facts and vocabulary, the typical non-science major student needs information presented in a way that is easy to read and understand. Even more importantly, the content should be meaningful. Students do much better when they understand why biology is relevant to their everyday lives. For these reasons, Concepts of Biology is grounded on an evolutionary basis and includes exciting features that highlight careers in the biological sciences and everyday applications of the concepts at hand.We also strive to show the interconnectedness of topics within this extremely broad discipline. In order to meet the needs of today's instructors and students, we maintain the overall organization and coverage found in most syllabi for this course. A strength of Concepts of Biology is that instructors can customize the book, adapting it to the approach that works best in their classroom. Concepts of Biology also includes an innovative art program that incorporates critical thinking and clicker questions to help students understand--and apply--key concepts.

Sex in animals has been known for at least ten thousand years, and this knowledge was put to good use during animal domestication in the Neolithic period. In stark contrast, sex in plants wasn't discovered until the late 17th century, long after the domestication of crop plants. Even after its discovery, the "sexual theory" continued to be hotly debated and lampooned for another 150 years, pitting the "sexualists" against the "asexualists". Why was the notion of sex in plants so contentious for so long? "Flora Unveiled" is a deep history of perceptions about plant gender and sexuality, beginning in the Ice Age and ending in the middle of the nineteenth century, with the elucidation of the complete plant life cycle. Linc and Lee Taiz show that a gender bias that plants are unisexual and female (a "one-sex model") prevented the discovery of plant sex and delayed its acceptance long after the theory was definitively proven. The book explores the various sources of this gender bias, beginning with women's role as gatherers, crop domesticators, and the first farmers. In the myths and religions of the Bronze and Iron Ages, female deities were strongly identified with flowers, trees, and agricultural abundance, and during Middle Ages and Renaissance, this tradition was assimilated into Christianity in the person of Mary. The one-sex model of plants continued into the Early Modern Period, and experienced a resurgence during the eighteenth century Enlightenment and again in the nineteenth century Romantic movement. Not until Wilhelm Hofmeister demonstrated the universality of sex in the plant kingdom was the controversy over plant sex finally laid to rest. Although "Flora Unveiled" focuses on the discovery of sex in plants, the history serves as a cautionary tale of how strongly and persistently cultural biases can impede the discovery and delay the acceptance of scientific advances.

Sex is the queen of problems in evolutionary biology. Generations of researchers have investigated one of the last remaining evolutionary paradoxes: why sex exists at all. Given that sexual reproduction is costly from an evolutionary point of view, one could wonder why not all animals and plants reproduce asexually. Dozens of contemporary hypotheses attempt to explain the prevalence of sex and its advantages and predict the early extinction of fully asexual lineages. The major theme of this book is: what is the fate of animal and plant groups in which sex is lost? Initial chapters discuss theory behind asexual life: what major disadvantages do asexual groups have to face, what are the genetic and ecological consequences and what does this theory predict for more applied aspects of asexual life, for example in agricultural pests, diseases as well as in cultural crops such as grapes. Cases studies in many animals (focusing on both invertebrates and vertebrates) and plants reveal parallel, but also singularly novel adaptations to the absence of meiosis and syngamy. And last but not least, are asexuals really doomed to early extinction or do genuine ancient asexuals exist? This book assembles contributions from the most important research groups dealing with asexual evolution in eukaryotes. It is a milestone in research on parthenogenesis and will be useful to undergraduate as well as graduate students and to senior researchers in all fields of evolutionary biology, as the paradox of sex remains its queen of problems.

A look into the phenomena of sex and reproduction in all organisms, taking an innovative, unified and comprehensive approach.