Definitions

biophysics

biophysics

[bahy-oh-fiz-iks]
biophysics, application of various methods and principles of physical science to the study of biological problems. In physiological biophysics physical mechanisms have been used to explain such biological processes as the transmission of nerve impulses, the muscle contraction mechanism, and the visual mechanism. Theoretical biophysics tries to use mathematical and physical models to explain life processes. Radiation biophysics studies the response of organisms to various kinds of radiations. Biophysics has contributed important tools for the study of organic molecules, and especially of large molecules, which play an important part in biological processes. Paper chromatography, a direct development of adsorption techniques, is widely used to analyze tissues for chemical components. X-ray crystallography is used to determine molecular structures and has been useful with such problems as the complex structure of proteins. Among the optical methods used in the study of biological problems are photochemistry, light scattering, absorption spectroscopy (including the use of visible, ultraviolet, and infrared radiation), laser beams, and double refraction birefringence. These techniques and others permit the biophysicist to determine the structure of molecules in plants and animals to a degree not readily possible with ordinary chemical methods.

Discipline concerned with applications of the principles and methods of the physical sciences to biological problems. Biophysics deals with biological functions that depend on physical agents such as electricity or mechanical force, with the interaction of living organisms with physical agents such as light, sound, or ionizing radiation, and with interactions between living things and their environment as in locomotion, navigation, and communication. Its subjects include bone, nerve impulses, muscle, and vision as well as organic molecules, using such tools as paper chromatography and X-ray crystallography.

Learn more about biophysics with a free trial on Britannica.com.

Biophysics (also biological physics) is an interdisciplinary science that employs and develops theories and methods of the physical sciences for the investigation of biological systems. Studies included under the umbrella of biophysics span all levels of biological organization, from the molecular scale to whole organisms and ecosystems. Biophysical research shares significant overlap with biochemistry, nanotechnology, bioengineering and systems biology.

Molecular biophysics typically address biological questions that are similar to those in biochemistry and molecular biology, but the questions are approached quantitatively. Scientists in this field conduct research concerned with understanding the interactions between the various systems of a cell, including the interactions between DNA, RNA and protein biosynthesis, as well as how these interactions are regulated. A great variety of techniques are used to answer these questions.

Fluorescent imaging techniques, as well as electron microscopy, x-ray crystallography, NMR spectroscopy and atomic force microscopy (AFM) are often used to visualize structures of biological significance. Direct manipulation of molecules using optical tweezers or AFM can also be used to monitor biological events where forces and distances are at the nanoscale. Molecular biophysicists often consider complex biological events as systems of interacting units which can be understood through statistical mechanics, thermodynamics and chemical kinetics. By drawing knowledge and experimental techniques from a wide variety of disciplines, biophysicists are often able to directly observe, model or even manipulate the structures and interactions of individual molecules or complexes of molecules.

In addition to traditional (i.e. molecular) biophysical topics like structural biology or enzyme kinetics, modern biophysics encompasses an extraordinarily broad range of research. It is becoming increasingly common for biophysicists to apply the models and experimental techniques derived from physics, as well as mathematics and statistics, to larger systems such as tissues, organs, populations and ecosystems.

Focus as a subfield

Biophysics often does not have university-level departments of its own, but has presence as groups across departments within the fields of molecular biology, biochemistry, chemistry, computer science, mathematics, medicine, pharmacology, physiology, physics, and neuroscience. What follows is a list of examples of how each department applies its efforts toward the study of biophysics. This list is hardly all inclusive. Nor does each subject of study belong exclusively to any particular department. Each academic institution makes its own rules and there is much overlap between departments.

Many biophysical techniques are unique to this field. Research efforts in biophysics are often initiated by scientists who were traditional physicists, chemists, and biologists by training.

Topics in biophysics and related fields

Famous biophysicists

Other notable biophysicists

References

  • Perutz M.F. Proteins and Nucleic Acids, Elsevier, Amsterdam, 1962
  • Perutz MF (1969). "The haemoglobin molecule". Proceedings of the Royal Society of London. Series B 173 (31): 113–40. PMID 4389425
  • Dogonadze R.R. and Urushadze Z.D. Semi-Classical Method of Calculation of Rates of Chemical Reactions Proceeding in Polar Liquids.- J.Electroanal.Chem., 32, 1971, pp. 235-245
  • Volkenshtein M.V., Dogonadze R.R., Madumarov A.K., Urushadze Z.D. and Kharkats Yu.I. Theory of Enzyme Catalysis.- Molekuliarnaya Biologia (Moscow), 6, 1972, pp. 431-439 (In Russian, English summary)
  • Rodney M. J. Cotterill (2002). Biophysics : An Introduction. Wiley.
  • Sneppen K. and Zocchi G., Physics in Molecular Biology, Cambridge University Press, 2005. ISBN 0-521-84419-3
  • Glaser R., Biophysics, Springer, 2001, ISBN 3-540-67088-2

See also

External links

Search another word or see Biophysicson Dictionary | Thesaurus |Spanish
Copyright © 2014 Dictionary.com, LLC. All rights reserved.
  • Please Login or Sign Up to use the Recent Searches feature
FAVORITES
RECENT

;