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Biochemistry
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Biochemistry, sometimes called biological chemistry, is the study of chemical processes within and relating to living organisms. By controlling information flow through biochemical signaling and the flow of energy through metabolism. Biochemistry is closely related to biology, the study of the molecular mechanisms by which genetic information encoded in DNA is able to result in the processes of life. Depending on the definition of the terms used, molecular biology can be thought of as a branch of biochemistry, or biochemistry as a tool with which to investigate. The chemistry of the cell depends on the reactions of smaller molecules. These can be inorganic, for water and metal ions, or organic, for example the amino acids. The mechanisms by which cells harness energy from their environment via chemical reactions are known as metabolism, the findings of biochemistry are applied primarily in medicine, nutrition, and agriculture. In medicine, biochemists investigate the causes and cures of diseases, in nutrition, they study how to maintain health and study the effects of nutritional deficiencies. In agriculture, biochemists investigate soil and fertilizers, and try to discover ways to improve crop cultivation, crop storage and pest control. However, biochemistry as a scientific discipline has its beginning sometime in the 19th century, or a little earlier. Gowland Hopkins on enzymes and the nature of biochemistry. The term biochemistry itself is derived from a combination of biology, the German chemist Carl Neuberg however is often cited to have coined the word in 1903, while some credited it to Franz Hofmeister. Then, in 1828, Friedrich Wöhler published a paper on the synthesis of urea and these techniques allowed for the discovery and detailed analysis of many molecules and metabolic pathways of the cell, such as glycolysis and the Krebs cycle. Another significant historic event in biochemistry is the discovery of the gene and this part of biochemistry is often called molecular biology. In the 1950s, James D. Watson, Francis Crick, Rosalind Franklin, in 1958, George Beadle and Edward Tatum received the Nobel Prize for work in fungi showing that one gene produces one enzyme. In 1988, Colin Pitchfork was the first person convicted of murder with DNA evidence, mello received the 2006 Nobel Prize for discovering the role of RNA interference, in the silencing of gene expression. Around two dozen of the 92 naturally occurring elements are essential to various kinds of biological life. Most rare elements on Earth are not needed by life, while a few common ones are not used, most organisms share element needs, but there are a few differences between plants and animals
2.
Biomolecule
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A more general name for this class of material is biological materials. Biomolecules are usually endogenous but may also be exogenous, for example, pharmaceutical drugs may be natural products or semisynthetic or they may be totally synthetic. Biology and its subsets of biochemistry and molecular biology study biomolecules, most biomolecules are organic compounds, and just four elements—oxygen, carbon, hydrogen, and nitrogen—make up 96% of the human bodys mass. But many other elements, such as the various biometals, are present in small amounts, examples of these include cytidine, uridine, adenosine, guanosine, thymidine and inosine. Nucleosides can be phosphorylated by specific kinases in the cell, producing nucleotides, both DNA and RNA are polymers, consisting of long, linear molecules assembled by polymerase enzymes from repeating structural units, or monomers, of mononucleotides. DNA uses the deoxynucleotides C, G, A, and T, while RNA uses the ribonucleotides C, G, A, modified bases are fairly common, as found in ribosomal RNA or transfer RNAs or for discriminating the new from old strands of DNA after replication. Each nucleotide is made of a nitrogenous base, a pentose. They contain carbon, nitrogen, oxygen, hydrogen and phosphorus and they serve as sources of chemical energy, participate in cellular signaling, and are incorporated into important cofactors of enzymatic reactions. DNA structure is dominated by the double helix formed by Watson-Crick base-pairing of C with G and A with T. This is known as B-form DNA, and is overwhelmingly the most favorable and common state of DNA, its highly specific and stable base-pairing is the basis of reliable genetic information storage. DNA can sometimes occur as single strands or as A-form or Z-form helices, RNA, in contrast, forms large and complex 3D tertiary structures reminiscent of proteins, as well as the loose single strands with locally folded regions that constitute messenger RNA molecules. Those RNA structures contain many stretches of A-form double helix, connected into definite 3D arrangements by single-stranded loops, bulges, examples are tRNA, ribosomes, ribozymes, and riboswitches. Monosaccharides are the simplest form of carbohydrates with only one simple sugar and they essentially contain an aldehyde or ketone group in their structure. The presence of an group in a monosaccharide is indicated by the prefix aldo-. Similarly, a group is denoted by the prefix keto-. Examples of monosaccharides are the hexoses glucose, fructose, and galactose and pentoses, ribose, most saccharides eventually provide fuel for cellular respiration. Disaccharides are formed when two monosaccharides, or two simple sugars, form a bond with removal of water. They can be hydrolyzed to yield their saccharin building blocks by boiling with dilute acid or reacting them with appropriate enzymes, examples of disaccharides include sucrose, maltose, and lactose
3.
Metabolism
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Metabolism is the set of life-sustaining chemical transformations within the cells of living organisms. These enzyme-catalyzed reactions allow organisms to grow and reproduce, maintain their structures, usually, breaking down releases energy and building up consumes energy. The chemical reactions of metabolism are organized into metabolic pathways, in one chemical is transformed through a series of steps into another chemical. Enzymes act as catalysts that allow the reactions to proceed more rapidly, enzymes also allow the regulation of metabolic pathways in response to changes in the cells environment or to signals from other cells. The metabolic system of a particular organism determines which substances it will find nutritious, for example, some prokaryotes use hydrogen sulfide as a nutrient, yet this gas is poisonous to animals. The speed of metabolism, the rate, influences how much food an organism will require. A striking feature of metabolism is the similarity of the metabolic pathways. These striking similarities in metabolic pathways are likely due to their appearance in evolutionary history. Most of the structures that make up animals, plants and microbes are made from three classes of molecule, amino acids, carbohydrates and lipids. These biochemicals can be joined together to make such as DNA and proteins. Proteins are made of amino acids arranged in a linear chain joined together by peptide bonds, many proteins are enzymes that catalyze the chemical reactions in metabolism. Other proteins have structural or mechanical functions, such as those that form the cytoskeleton, Proteins are also important in cell signaling, immune responses, cell adhesion, active transport across membranes, and the cell cycle. Lipids are the most diverse group of biochemicals and their main structural uses are as part of biological membranes both internal and external, such as the cell membrane, or as a source of energy. Lipids are usually defined as hydrophobic or amphipathic biological molecules but will dissolve in organic solvents such as benzene or chloroform, the fats are a large group of compounds that contain fatty acids and glycerol, a glycerol molecule attached to three fatty acid esters is called a triacylglyceride. Several variations on this structure exist, including alternate backbones such as sphingosine in the sphingolipids. Steroids such as cholesterol are another class of lipids. Carbohydrates are aldehydes or ketones, with hydroxyl groups attached. Carbohydrates are the most abundant biological molecules, and fill numerous roles, such as the storage and transport of energy, the basic carbohydrate units are called monosaccharides and include galactose, fructose, and most importantly glucose
4.
History of biochemistry
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The term “biochemistry” itself is derived from the combining form bio-, meaning life, and chemistry. Nevertheless, several sources cite German chemist Carl Neuberg as having coined the term for the new discipline in 1903, and some credit it to Franz Hofmeister. Over the last 40 years the field has had success in explaining living processes such that now almost all areas of the life sciences from botany to medicine are engaged in biochemical research. Among the vast number of different biomolecules, many are complex and large molecules, each class of polymeric biomolecule has a different set of subunit types. Biochemistry studies the properties of important biological molecules, like proteins. The biochemistry of cell metabolism and the system has been extensively described. Other areas of biochemistry include the code, protein synthesis, cell membrane transport. It began in the ancient Indian culture also with an interest in medicine and they also delved into the interest of bodies being composed of tissues. On the side of chemistry, early advancements were heavily attributed to exploration of interests but also included, metallurgy, the scientific method. In more recent times, the study of chemistry was marked by such as the development of Mendeleevs periodic table, Daltons atomic model. This last mention has the most importance of the three due to the fact that this law intertwines chemistry with thermodynamics in an intercalated manner. As early as the late 18th century and early 19th century, the digestion of meat by stomach secretions, however, the mechanism by which this occurred had not been identified. He wrote that alcoholic fermentation is an act correlated with the life and organization of the yeast cells, the word enzyme was used later to refer to nonliving substances such as pepsin, and the word ferment used to refer to chemical activity produced by living organisms. In 1897 Eduard Buchner began to study the ability of yeast extracts to ferment sugar despite the absence of living yeast cells. In a series of experiments at the University of Berlin, he found that the sugar was fermented even when there were no living yeast cells in the mixture and he named the enzyme that brought about the fermentation of sucrose zymase. In 1907 he received the Nobel Prize in Chemistry for his biochemical research, following Buchners example, enzymes are usually named according to the reaction they carry out. Typically the suffix -ase is added to the name of the substrate or the type of reaction, having shown that enzymes could function outside a living cell, the next step was to determine their biochemical nature. Sumner showed that the enzyme urease was a protein and crystallized it
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Bioinformatics
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Bioinformatics /ˌbaɪ. oʊˌɪnfərˈmætɪks/ is an interdisciplinary field that develops methods and software tools for understanding biological data. As an interdisciplinary field of science, bioinformatics combines computer science, statistics, mathematics, Bioinformatics has been used for in silico analyses of biological queries using mathematical and statistical techniques. Common uses of bioinformatics include the identification of genes and nucleotides. Often, such identification is made with the aim of understanding the genetic basis of disease, unique adaptations, desirable properties. In a less formal way, bioinformatics also tries to understand the principles within nucleic acid and protein sequences. Bioinformatics has become an important part of areas of biology. In experimental molecular biology, bioinformatics techniques such as image and signal processing allow extraction of useful results from large amounts of raw data, in the field of genetics and genomics, it aids in sequencing and annotating genomes and their observed mutations. It plays a role in the mining of biological literature. It also plays a role in the analysis of gene and protein expression and regulation, Bioinformatics tools aid in the comparison of genetic and genomic data and more generally in the understanding of evolutionary aspects of molecular biology. At a more level, it helps analyze and catalogue the biological pathways. In structural biology, it aids in the simulation and modeling of DNA, RNA, historically, the term bioinformatics did not mean what it means today. Paulien Hogeweg and Ben Hesper coined it in 1970 to refer to the study of processes in biotic systems. This definition placed bioinformatics as a parallel to biophysics or biochemistry. Computers became essential in molecular biology when protein sequences became available after Frederick Sanger determined the sequence of insulin in the early 1950s, comparing multiple sequences manually turned out to be impractical. A pioneer in the field was Margaret Oakley Dayhoff, who has been hailed by David Lipman, director of the National Center for Biotechnology Information, Dayhoff compiled one of the first protein sequence databases, initially published as books and pioneered methods of sequence alignment and molecular evolution. To study how normal cellular activities are altered in different disease states, therefore, the field of bioinformatics has evolved such that the most pressing task now involves the analysis and interpretation of various types of data. This includes nucleotide and amino acid sequences, protein domains, the actual process of analyzing and interpreting data is referred to as computational biology. For example, there are methods to locate a gene within a sequence, to predict protein structure and/or function, the primary goal of bioinformatics is to increase the understanding of biological processes
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Enzyme
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Enzymes /ˈɛnzaɪmz/ are macromolecular biological catalysts. Enzymes accelerate, or catalyze, chemical reactions, the molecules at the beginning of the process upon which enzymes may act are called substrates and the enzyme converts these into different molecules, called products. Almost all metabolic processes in the cell need enzymes in order to occur at rates fast enough to sustain life, the set of enzymes made in a cell determines which metabolic pathways occur in that cell. The study of enzymes is called enzymology, enzymes are known to catalyze more than 5,000 biochemical reaction types. Most enzymes are proteins, although a few are catalytic RNA molecules, enzymes specificity comes from their unique three-dimensional structures. Like all catalysts, enzymes increase the rate of a reaction by lowering its activation energy, some enzymes can make their conversion of substrate to product occur many millions of times faster. An extreme example is orotidine 5-phosphate decarboxylase, which allows a reaction that would take millions of years to occur in milliseconds. Chemically, enzymes are like any catalyst and are not consumed in chemical reactions, enzymes differ from most other catalysts by being much more specific. Enzyme activity can be affected by other molecules, inhibitors are molecules that decrease enzyme activity, many drugs and poisons are enzyme inhibitors. An enzymes activity decreases markedly outside its optimal temperature and pH, some enzymes are used commercially, for example, in the synthesis of antibiotics. French chemist Anselme Payen was the first to discover an enzyme, diastase and he wrote that alcoholic fermentation is an act correlated with the life and organization of the yeast cells, not with the death or putrefaction of the cells. In 1877, German physiologist Wilhelm Kühne first used the term enzyme, the word enzyme was used later to refer to nonliving substances such as pepsin, and the word ferment was used to refer to chemical activity produced by living organisms. Eduard Buchner submitted his first paper on the study of yeast extracts in 1897, in a series of experiments at the University of Berlin, he found that sugar was fermented by yeast extracts even when there were no living yeast cells in the mixture. He named the enzyme that brought about the fermentation of sucrose zymase, in 1907, he received the Nobel Prize in Chemistry for his discovery of cell-free fermentation. Following Buchners example, enzymes are usually named according to the reaction they carry out, the biochemical identity of enzymes was still unknown in the early 1900s. Sumner showed that the enzyme urease was a protein and crystallized it. These three scientists were awarded the 1946 Nobel Prize in Chemistry, the discovery that enzymes could be crystallized eventually allowed their structures to be solved by x-ray crystallography. This high-resolution structure of lysozyme marked the beginning of the field of structural biology, an enzymes name is often derived from its substrate or the chemical reaction it catalyzes, with the word ending in -ase
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Genetics
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Genetics is the study of genes, genetic variation, and heredity in living organisms. It is generally considered a field of biology, but intersects frequently with other life sciences and is strongly linked with the study of information systems. The father of genetics is Gregor Mendel, a late 19th-century scientist, Mendel studied trait inheritance, patterns in the way traits are handed down from parents to offspring. He observed that organisms inherit traits by way of discrete units of inheritance and this term, still used today, is a somewhat ambiguous definition of what is referred to as a gene. Gene structure and function, variation, and distribution are studied within the context of the cell, the organism, genetics has given rise to a number of subfields, including epigenetics and population genetics. Organisms studied within the broad field span the domain of life, including bacteria, plants, animals, genetic processes work in combination with an organisms environment and experiences to influence development and behavior, often referred to as nature versus nurture. The intracellular or extracellular environment of a cell or organism may switch gene transcription on or off, a classic example is two seeds of genetically identical corn, one placed in a temperate climate and one in an arid climate. The word genetics stems from the ancient Greek γενετικός genetikos meaning genitive/generative, the observation that living things inherit traits from their parents has been used since prehistoric times to improve crop plants and animals through selective breeding. The modern science of genetics, seeking to understand this process, prior to Mendel, Imre Festetics, a Hungarian noble, who lived in Kőszeg before Mendel, was the first who used the word genetics. He described several rules of inheritance in his work The genetic law of the Nature. His second law is the same as what Mendel published, in his third law, he developed the basic principles of mutation. Other theories of inheritance preceded his work, a popular theory during Mendels time was the concept of blending inheritance, the idea that individuals inherit a smooth blend of traits from their parents. Mendels work provided examples where traits were not blended after hybridization. Blending of traits in the progeny is now explained by the action of genes with quantitative effects. Another theory that had some support at that time was the inheritance of acquired characteristics, other theories included the pangenesis of Charles Darwin and Francis Galtons reformulation of pangenesis as both particulate and inherited. Modern genetics started with Gregor Johann Mendel, a scientist and Augustinian friar who studied the nature of inheritance in plants, the importance of Mendels work did not gain wide understanding until the 1890s, after his death, when other scientists working on similar problems re-discovered his research. William Bateson, a proponent of Mendels work, coined the word genetics in 1905, Bateson popularized the usage of the word genetics to describe the study of inheritance in his inaugural address to the Third International Conference on Plant Hybridization in London in 1906. After the rediscovery of Mendels work, scientists tried to determine which molecules in the cell were responsible for inheritance, in 1911, Thomas Hunt Morgan argued that genes are on chromosomes, based on observations of a sex-linked white eye mutation in fruit flies
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Immunology
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Immunology is a branch of biology that covers the study of immune systems in all organisms. It was the Russian biologist Ilya Ilyich Mechnikov who boosted studies on immunology and he jabbed the thorn of a rose on a starfish and noted that,24 hours later, cells were surrounding the tip. It was a response of the body, trying to maintain its integrity. It was Mechnikov who first observed the phenomenon of phagocytosis, in which the body defends itself against a foreign body, Immunology has applications in numerous disciplines of medicine, particularly in the fields of organ transplantation, oncology, virology, bacteriology, parasitology, psychiatry, and dermatology. The important lymphoid organs of the system are the thymus and bone marrow, and chief lymphatic tissues such as spleen, tonsils, lymph vessels, lymph nodes, adenoids. Classical immunology ties in with the fields of epidemiology and medicine and it studies the relationship between the body systems, pathogens, and immunity. The earliest written mention of immunity can be traced back to the plague of Athens in 430 BCE, thucydides noted that people who had recovered from a previous bout of the disease could nurse the sick without contracting the illness a second time. Many other ancient societies have references to this phenomenon, but it was not until the 19th and 20th centuries before the concept developed into scientific theory. The study of the molecular and cellular components that comprise the immune system, the immune system has been divided into a more primitive innate immune system and, in vertebrates, an acquired or adaptive immune system. The latter is divided into humoral and cell-mediated components. The humoral response is defined as the interaction between antibodies and antigens, antibodies are specific proteins released from a certain class of immune cells known as B lymphocytes, while antigens are defined as anything that elicits the generation of antibodies. Immunology rests on an understanding of the properties of two biological entities and the cellular response to both. Immunological research continues to more specialized, pursuing non-classical models of immunity and functions of cells, organs. Clinical immunology is the study of diseases caused by disorders of the immune system and it also involves diseases of other systems, where immune reactions play a part in the pathology and clinical features. Other immune system include various hypersensitivities that respond inappropriately to otherwise harmless compounds. Clinical immunologists also study ways to prevent the immune systems attempts to destroy allografts, the body’s capability to react to antigen depends on a persons age, antigen type, maternal factors and the area where the antigen is presented. Neonates are said to be in a state of physiological immunodeficiency, once born, a child’s immune system responds favorably to protein antigens while not as well to glycoproteins and polysaccharides. In fact, many of the infections acquired by neonates are caused by low virulence organisms like Staphylococcus, in neonates, opsonic activity and the ability to activate the complement cascade is very limited
This article incorporates public domain material from the NCBI document "Science Primer".
This article incorporates 
