Introduction to Biochemistry - II

What is Biochemistry? Biochemistry is defined as the science concerned with the chemical basis of life (Greek bios means “life”). Biochemistry deals about the chemistry of living cells. Every aspect of life depends upon the chemical makeup of cells and on the chemical properties of the remarkable molecules found within the cells. Biochemistry asks how the remarkable properties of living organisms arise from the thousands of different lifeless biomolecules. When these molecules are isolated and examined individually, they conform to all the physical and chemical laws that describe the behavior of inanimate matter—as do all the processes occurring in living organisms. The study of biochemistry shows how the collections of the inanimate molecules that constitute living organisms interact to maintain and perpetuate life . How old is Biochemistry? Organisms are remarkably uniform at the molecular level. All organisms are built from similar molecular components distinguishable by relatively minor variations. This uniformity reveals that all organisms on Earth have arisen from a common ancestor. A core of essential biochemical processes, common to all organisms, appeared early in the evolution of life. The diversity of life in the modern world has been generated by evolutionary processes acting on these core processes through millions or even billions of years. The cell is the structural unit of living systems. Thus, biochemistry can also be described as the science concerned with the chemical constituents of living cells and with the reactions and processes they undergo. By this definition, biochemistry encompasses large areas of cell biology, of molecular biology, and of molecular genetics. What is the relationship with other subjects? Physiology, the study of body function, overlaps with biochemistry almost completely. Immunology employs numerous biochemical techniques, and many immunologic approaches have found wide use by biochemists. Pharmacology and pharmacy rest on a sound knowledge of biochemistry and physiology; in particular, most drugs are metabolized by enzyme-catalyzed reactions. Poisons act on biochemical reactions or processes; this is the subject matter of toxicology. Biochemical approaches are being used increasingly to study basic aspects of pathology (the study of disease), such as inflammation, cell injury, and cancer. Many workers in microbiology, zoology, and botany employ biochemical approaches almost exclusively. These relationships are not surprising, because life as we know it depends on biochemical reactions and processes. In fact, the old barriers among the life sciences are breaking down, and biochemistry is increasingly becoming their common language. Biochemical studies have thrown light upon many aspects of health and disease, and conversely, the study of various aspects of health and disease has opened up new areas of biochemistry. What is waiting for Biochemistry in future? By examining biochemistry in the context of life, we can often understand how particular molecules or processes helped organisms adapt to specific environments or life styles. We can ask not only what biochemical processes take place, but also why particular strategies appeared in the course of evolution. In addition to being sources of historical insights, the answers to such questions are often highly instructive with regard to the biochemistry of contemporary organisms. For more details Biochemistry visit my webpage at Biochemistry Online