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BiologyBiology is a natural science concerned with the study of life and living organisms,including their structure, function, growth, evolution, distribution, and taxonomy.[1] Biology has many subdisciplines unified by five so-calledaxioms of modern biology:[2]

1. Cells are the basic unit of life2.

Genes are the basic unit of heredity3. New species and inherited traits are the product of evolution4.  An organism regulates its internal environment to maintain a stable and constant

condition5. Living organisms consume and transform energy

Subdisciplines of biology are defined by the scale at which organisms are studied andthe methods used to study them: biochemistry examines the rudimentary chemistry of life; molecular biology studies the complex interactions amongbiological molecules; cellular biology examines the basic building block of all life,the cell; physiology examines the physical and chemical functions of tissues, organs,and organ systems of an organism;evolutionary biology examines the processes that

produced the diversity of life; and ecology examines how organisms interact intheir environment.[3]

Scope of BiologyBiology reveals to us the secretes of life uncovered by biologist through centuries of researches.Biology is of great importance to mankind in a practical sense.Young biologists to choose their field of specialization is called scope of Biology. Thescopes are:-

AnthropologyThe science of man and mankind including the study of the physical and mental

constitution of man.It also deals cultural development, social condition, as exhibited by both in present andpast.

Biomedical engineeringBranch of engineering dealing with the production of spare parts for man.

 Artificial limbs, heart, lungs and other machines to help impaired body funtions are theproduct of Bio medical engineering used by the doctors.

BiotechnologyIt deals with the use of living organisms or of substances obtained from them inindustrial process.

Food technologyThe science of processing and preservation of healthy foods.The application of science for the manufacture of milk products is called Dairytechnology.Culture: the rearing of honey bees, bee keeping especially for commercial purposes.Fishery or Pisiculture : The industry of rearing and catching fishes or other products of 

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the sea, lakes, rivers or ponds.Sericulture : the breeding and treatment of silkworms for producing raw silk.Entomology deals with the structure, habits, and classification of insects.

Genetic Engineering

It involves genetic manipulation to produce an organism with a new combination toimprove the heredity.The production of improved varities by selecting mating is called breeding.

 Application of scientific knowledge to question civil and criminal laws is called forensicscience.

Vetenary MedicineIt deals with the study of domesticated animals and their health care.Science dealing with the rearing of domestic fowls such as chickens, ducks and geeseare called poultry science.

MedicineThe science of treating diseases with drugs or curative substances.The science dealing with structure, function and use of microscopic organisms is calledmicrobiology.The science dealing with the nature of diseases their causes, symptoms and effects iscalled pathology.The branch of medicine, involving physical operations to cure diseases or injuries to thebody is called Surgery.The science of knowledge of drugs and preparation of medicine is called pharmacology.

Therapy

 A method of treatment of convalescents and for physically handicapped utilizing lightwork for diversion, physical exercise or vocational training is called occupationaltherapy.The treatment of diseases, bodily weakness or defects by physical remedies, such asmassage and exercise called physiotherapy.

CHEMISTRYChemistry, a branch of physical science, is the study of the composition, properties andbehavior of matter .[1][2] Chemistry is concerned with atoms and their interactions withother atoms, and particularly with the properties of chemical bonds. Chemistry is alsoconcerned with the interactions between atoms (or groups of atoms) and various formsof energy (e.g. photochemical reactions, changes in phases of matter, separation of mixtures, properties of polymers, etc.).Chemistry is sometimes called "the central science" because it bridges other naturalsciences like physics, geology and biology with each other.[3][4] Chemistry is a branchof physical science but distinct from physics.[5]

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The etymology of the word chemistry has been much disputed. [6] The genesis of chemistry can be traced to certain practices, known as alchemy, which had beenpracticed for severalmillennia in various parts of the world, particularly the Middle East.[7]

chemistry, the science that deals with the properties, composition, and structure of substances (defined as elements and compounds), the transformations they undergo,

and the energy that is released or absorbed during these processes. Every substance,whether naturally occurring or artificially produced, consists of one or more of thehundred-odd species of atoms that have been identified as elements. Although theseatoms, in turn, are composed of more elementary particles, they are the basic buildingblocks of chemical substances; there is no quantity of oxygen, mercury, or gold, for example, smaller than an atom of that substance. Chemistry, therefore, is concernednot with the subatomic domain but with the properties of atoms and the laws governingtheir combinations and how the knowledge of these properties can be used to achievespecific purposes.The great challenge in chemistry is the development of a coherent explanation of thecomplex behaviour of materials, why they appear as they do, what gives them their 

enduring properties, and how interactions among different substances can bring aboutthe formation of new substances and the destruction of old ones. From the earliestattempts to understand the material world in rational terms, chemists have struggled todevelop theories of matter that satisfactorily explain both permanence and change. Theordered assembly of indestructible atoms into small and large molecules, or extendednetworks of intermingled atoms, is generally accepted as the basis of permanence,while the reorganization of atoms or molecules into different arrangements lies behindtheories of change. Thus chemistry involves the study of the atomic composition andstructural architecture of substances, as well as the varied interactions amongsubstances that can lead to sudden, often violent reactions.Chemistry also is concerned with the utilization of natural substances and the creation

of artificial ones. Cooking, fermentation, glass making, and metallurgy are all chemicalprocesses that date from the beginnings of civilization. Today, vinyl, Teflon, liquidcrystals, semiconductors, and superconductors represent the fruits of chemicaltechnology. The 20th century has seen dramatic advances in the comprehension of themarvelous and complex chemistry of living organisms, and a molecular interpretation of health and disease holds great promise. Modern chemistry, aided by increasinglysophisticated instruments, studies materials as small as single atoms and as large andcomplex as DNA (deoxyribonucleic acid), which contains millions of atoms. Newsubstances can even be designed to bear desired characteristics and then synthesized.The rate at which chemical knowledge continues to accumulate is remarkable. Over time more than 8,000,000 different chemical substances, both natural and artificial,have been characterized and produced. The number was less than 500,000 as recentlyas 1965.Intimately interconnected with the intellectual challenges of chemistry are thoseassociated with industry. In the mid-19th century the German chemist Justusvon Liebig commented that the wealth of a nation could be gauged by the amountof sulfuric acid it produced. This acid, essential to many manufacturing processes,remains today the leading chemical product of industrialized countries. As Liebigrecognized, a country that produces large amounts of sulfuric acid is one with a strong

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chemical industry and a strong economy as a whole. The production, distribution, andutilization of a wide range of chemical products is common to all highly developednations. In fact, one can say that the “iron age” of civilization is being replaced by a“polymer age,” for in some countries the total volume of polymers now producedexceeds that of iron.

Table Of ContentsThe scope of chemistry 

The days are long past when one person could hope to have a detailed knowledge of allareas of chemistry. Those pursuing their interests into specific areas of chemistrycommunicate with others who share the same interests. Over time a group of chemistswith specialized research interests become the founding members of an area of specialization. The areas of specialization that emerged early in the history of chemistry,such as organic, inorganic, physical, analytical, and industrial chemistry, along withbiochemistry, remain of greatest general interest. There has been, however, muchgrowth in the areas of polymer, environmental, and medicinal chemistry during the 20thcentury. Moreover, new specialities continue to appear, as, for example, pesticide,

forensic, and computer chemistry.Analytical chemistryMost of the materials that occur on Earth, such as wood, coal, minerals, or air, aremixtures of many different and distinct chemical substances. Each pure chemicalsubstance (e.g., oxygen, iron, or water) has a characteristic set of properties that givesit its chemical identity. Iron, for example, is a common silver-white metal that melts at1,535° C, is very malleable, and readily combines with oxygen to form the commonsubstances hematite and magnetite. The detection of iron in a mixture of metals, or in acompound such as magnetite, is a branch of analytical chemistry called qualitativeanalysis. Measurement of the actual amount of a certain substance in a compound or mixture is termed quantitative analysis. Quantitative analytic measurement has

determined, for instance, that iron makes up 72.3 percent, by mass, of magnetite, themineral commonly seen as black sand along beaches and stream banks. Over theyears, chemists have discovered chemical reactions that indicate the presence of suchelemental substances by the production of easily visible and identifiable products. Ironcan be detected by chemical means if it is present in a sample to an amount of 1 partper million or greater. Some very simple qualitative tests reveal the presence of specificchemical elements in even smaller amounts. The yellow colour imparted to a flame bysodium is visible if the sample being ignited has as little as one-billionth of a gram of sodium. Such analytic tests have allowed chemists to identify the types and amounts of impurities in various substances and to determine the properties of very pure materials.Substances used in common laboratory experiments generally have impurity levels of 

less than 0.1 percent. For special applications, one can purchase chemicals that haveimpurities totaling less than 0.001 percent. The identification of pure substances and theanalysis of chemical mixtures enable all other chemical disciplines to flourish.The importance of analytical chemistry has never been greater than it is today. Thedemand in modern societies for a variety of safe foods, affordable consumer goods,abundant energy, and labour-saving technologies places a great burden on theenvironment. All chemical manufacturing produces waste products in addition to thedesired substances, and waste disposal has not always been carried out carefully.

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Disruption of the environment has occurred since the dawn of civilization, and pollutionproblems have increased with the growth of global population. The techniques of analytical chemistry are relied on heavily to maintain a benign environment. Theundesirable substances in water, air, soil, and food must be identified, their point of origin fixed, and safe, economical methods for their removal or neutralization

developed. Once the amount of a pollutant deemed to be hazardous has beenassessed, it becomes important to detect harmful substances at concentrations wellbelow the danger level. Analytical chemists seek to develop increasingly accurate andsensitive techniques and instruments.Sophisticated analytic instruments, often coupled with computers, have improved theaccuracy with which chemists can identify substances and have lowered detectionlimits. An analytic technique in general use is gas chromatography, which separates thedifferent components of a gaseous mixture by passing the mixture through a long,narrow column of absorbent but porous material. The different gases interact differentlywith this absorbent material and pass through the column at different rates. As theseparate gases flow out of the column, they can be passed into another analytic

instrument called a mass spectrometer , which separates substances according to themass of their constituent ions. A combined gas chromatograph–mass spectrometer canrapidly identify the individual components of a chemical mixture whose concentrationsmay be no greater than a few parts per billion. Similar or even greater sensitivities canbe obtained under favourable conditions using techniques such as atomic absorption,polarography, and neutron activation. The rate of instrumental innovation is such thatanalytic instruments often become obsolete within 10 years of their introduction. Newer instruments are more accurate and faster and are employed widely in the areas of environmental and medicinal chemistry.

PHYSICS

Physics (from Ancient Greek: φύσις physis "nature") is a part of natural philosophy anda natural science that involves the study of matter [1] and itsmotion through space andtime, along with related concepts such as energyand force.[2] More broadly, it is thegeneral analysis of nature, conducted in order to understand how the universe behaves.[3][4][5]

Physics is one of the oldest academic disciplines, perhaps the oldest through itsinclusion of astronomy.[6] Over the last two millennia, physics was a part of naturalphilosophy along with chemistry, certain branches of mathematics, andbiology, butduring the Scientific Revolution in the 17th century, the natural sciences emerged asunique research programs in their own right.[7] Physics intersects withmany interdisciplinary areas of research, such as biophysicsand quantum chemistry,and the boundaries of physics are not rigidly defined. New ideas in physics often explainthe fundamental mechanisms of other sciences, while opening new avenues of research in areas such as mathematics and philosophy.Physics also makes significant contributions through advances in new technologiesthatarise from theoretical breakthroughs. For example, advances in the understandingof electromagnetism or nuclear physics led directly to the development of new productswhich have dramatically transformed modern-day society, such

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as television, computers, domestic appliances, and nuclear weapons; advancesin thermodynamics led to the development of industrialization; and advancesin mechanics inspired the development of calculus.Physics is the broadest of the sciences. In the 1800's it was called Natural Philosophy.It is the description of "how the natural world works". Physics comprises astronomy,

electronics, optics, thermodynamics, hydraulics, mechanics (statics and dynamics),atomic theory, cosmology, physical chemistry. and other fields.Some sciences like biology, organic and inorganic chemistry, botany, zoology,physiology, etc. are all physics at their base, although they are studied at a much higher level.Formerly called natural philosophy, physics is concerned with those aspects of nature which can be understood in a fundamental way in terms of elementary principlesand laws. In the course of time, various specialized sciences broke away from physicsto form autonomous fields of investigation. In this process physics retained its originalaim of understanding the structure of the natural world and explaining naturalphenomena.The most basic parts of physics are mechanics and field theory. Mechanics is

concerned with the motion of particles or bodies under the action of given forces. Thephysics of fields is concerned with the origin, nature, and properties of gravitational,electromagnetic, nuclear, and other force fields. Taken together, mechanics and fieldtheory constitute the most fundamental approach to an understanding of naturalphenomena which science offers. The ultimate aim is to understand all naturalphenomena in these terms. See also Classical field theory; Mechanics; Quantum fieldtheory.The older, or classical, divisions of physics were based on certain general classes of natural phenomena to which the methods of physics had been found particularlyapplicable. The divisions are all still current, but many of them tend more and more todesignate branches of applied physics or technology, and less and less inherent

divisions in physics itself. The divisions or branches, of modern physics are made inaccordance with particular types of structures in nature with which each branch isconcerned.In every area physics is characterized not so much by its subject-matter content as bythe precision and depth of understanding which it seeks. The aim of physics is theconstruction of a unified theoretical scheme in mathematical terms whose structure andbehavior duplicates that of the whole natural world in the most comprehensive manner possible. Where other sciences are content to describe and relate phenomena in termsof restricted concepts peculiar to their own disciplines, physics always seeks tounderstand the same phenomena as a special manifestation of the underlying uniformstructure of nature as a whole. In line with this objective, physics is characterized byaccurate instrumentation, precision of measurement, and the expression of its results inmathematical terms.For the major areas of physics and for additional listings of articles in physics See also

 Acoustics; Atomic physics; Biophysics; Classical mechanics; Electricity;Electromagnetism; Elementary particle; Fluid mechanics; Heat; Low-temperaturephysics; Molecular physics; Nuclear physics; Optics; Solid-state physics; Statisticalmechanics.