Biology is the science life. Biology is the story of life on earth. Biology is the science of life forms and living processes. The term Biology was introduced in Germany in 1800 and popularized by the French naturalist Jean-Baptiste de Lamarck as a means of encompassing the growing number of disciplines involved with the study of living forms. The unifying concept of biology received its greatest stimulus from the English zoologist Thomas Henry Huxley, who was also an important educator. Huxley insisted that the conventional segregation of zoology and botany was intellectually meaningless and that all living things should be studied in an integrated way. Huxley’s approach to the study of biology is even more cogent today, because scientists now realize that many lower organisms are neither plants nor animals (see Prokaryote; Protista). The limits of the science, however, have always been difficult to determine, and as the scope of biology has shifted over the years, its subject areas have been changed and reorganized. Today biology is subdivided into hierarchies based on the molecule, the cell, the organism, and the population. Biological system, often appear to challenge physical laws that govern the behaviour of matter and energy in our world. Historically, biological knowledge was ancillary to knowledge of human body and its function. The latter as we know, is the basis of medical practice. However, parts of biological knowledge developed independent of human application. Fundamental question about origin of life, the origin and growth of biodiversity, the evolution of flora and fauna of different habitats, etc., caught the imagination of biologists. Molecular biology, which spans biophysics and biochemistry, has made the most fundamental contributions to modern biology. Much is now known about the structure and action of nucleic acids and protein, the key molecules of all living matter. The discovery of the mechanism of heredity was a major breakthrough in modern science. Another important advance was in understanding how molecules conduct metabolism, that is, how they process the energy needed to sustain life. Cellular biology is closely linked with molecular biology. To understand the functions of the cell—the basic structural unit of living matter—cell biologists study its components on the molecular level. Organismal biology, in turn, is related to cellular biology, because the life functions of multicellular organisms are governed by the activities and interactions of their cellular components. The study of organisms includes their growth and development (developmental biology) and how they function (physiology). Particularly important are investigations of the brain and nervous system (neurophysiology) and animal behavior (ethology). Population biology became firmly established as a major subdivision of biological studies in the 1970s. Central to this field is evolutionary biology, in which the contributions of Charles Darwin have been fully appreciated after a long period of neglect. Population genetics, the study of gene changes in populations, and ecology, the study of populations in their natural habitats, have been established subject areas since the 1930s. These two fields were combined in the 1960s to form a rapidly developing new discipline often called, simply, population biology. Closely associated is a new development in animal-behavior studies called sociobiology, which focuses on the genetic contribution to social interactions among animal populations. The very description of living organisms is it forms morphological perspective, physiological perspective, taxonomical perspective, etc., engaged scientists to such an extent that for sheer convenience, if not for anything else, the subject matter got artificially divided into the sub-disciplines of botany and zoology and later into even microbiology. Meanwhile, physical sciences made heavy inroads into biology, and established biochemistry and biophysics as new sub-discipline of biology. Mendel’s work and its rediscovery in the early twentieth century led to the promotion of study of genetics. The discovery of the double-helical structure of DNA (deoxyribose nucleic acid) and the deciphering of three dimensional structures of many macromolecules led to the establishment of and phenomenal growth in the dominating area of molecular biology. In a sense, functional discipline laying emphasis on mechanism underlying living processes, received more attention, support, intellectual and social recognition. Biology, unfortunately, got divided into classical and modern biology. To the majority of practicing biologists, pursuit of biological research became more empirical rather than a curiosity and hypothesis driven intellectual exercise as is the case with theoretical physics, experimental physics, structural chemistry and material science. Fortunately and quietly, general unifying principles of biology were also being discovered, rediscovered and emphasized. The work of Mayr, Dobhzhansky, Haldane, Perutz, Khorana, Morgan, Darlington, Fisher and many others brought respect and seriousness to both classical and molecular biological disciplines. Ecology and systems biology got establishment as unifying biological disciplines. Every area of biology began developing interface with not only other areas of biology but also other disciplines of science and mathematics. Pretty soon, the boundaries became porous. They are now on the verge of disappearing altogether. Progress in human biology, biomedical sciences, especially the structure, functioning and evolution of human brain brought in respect, awe and philosophical insights to biology. Biology even stepped out of laboratories, museums and natural parks and raised social, economic and cultural issues capturing the imagination of general public and hence political attention. Educationists did not lag behind and realized that biology should be taught as an interdisciplinary and integrating science at all stages of educational training especially at school and undergraduate levels. A new synthesis of all areas of basic and applied areas of biology is the need of the hour. Biology has come of age. It has an independent set of concepts which are universal just like physics and chemistry and mathematics. The present articles are the first time presentation of integrated biology for school level children. One of the lacunae in biology teaching and study is the absence of integration with other disciplinary knowledge of physics, chemistry etc. further many processes in plants, animals and microbes are similar when looked from physic-chemical perspective. Cell biology has brought out the unifying common cellular level activities underlying apparently diverse phenomena across plants, animals and microbes. Similarly, molecular science (e.g. biochemistry or molecular biology) has revealed the similar molecular mechanisms in all these apparently diverse organisms like plants, animals, and microbes. Phenomena like respiration, metabolism, energy utilization, growth, reproduction and development can be discussed in a unifying manner rather than as separate unrelated processes in plants and animals. An attempt has been made to unify such diverse disciplines in the articles. The integration achieved however, is partial and not complete. Hopefully along with changes in the teaching and learning context, to be brought out in the next few years, the next edition of these articles will reveal more integration of botany, zoology and microbiology and truly reflect the true nature of biology– the future science of man by man and for women.