A description of the wavelength dependence of effects introduced by electromagnetic radiation on biological matter. For example, a sunburn action spectrum describes the degree to which varying wavelengths of ultraviolet rays inflict sunburn. It is usually displayed as a function on a graph.
the efficiency with which electromagnetic radiation produces a photochemical reaction plotted as a function of the wavelength of the radiation
a graph of the reciprocal of the radiant exposure required to produce the given effect at each wavelength
a parameter function which describes the relative effect of energy at different wavelengths in producing a certain biological response
a parameter that describes the relative effectiveness of energy at different wavelengths in producing a particular biological response
a plot of the relative effectiveness of radiation of different wavelengths to produce a given biological effect
The action spectrum is a quantitative indication of the relative biological or chemical photoresponse, per number of incident photons, as a function of wavelength or energy of radiation under the same incident fluence rate. Many microorganisms have a disinfection action spectrum that is very similar to the absorption spectrum of DNA, while others have different action spectra. Ideally, one should use the action spectrum appropriate to the microorganism of interest. Unfort¬unately, in most cases the appropriate action spectrum is not known. In such cases, it is acceptable to assume that the action spectrum is proportional to that of the absorbance of DNA.
An action spectrum is the rate of a physiological activity plotted against wavelength of light. It shows which wavelength of light is most effectively used in a specific chemical reaction. Some reactants are able to use specific wavelengths of light more effectively to complete their reactions.