<P> In vitro was among the first attempts to qualitatively and quantitatively analyze natural occurrences in the lab . Eventually, the limitation of in vitro experimentation was that they were not conducted in natural environments . To compensate for this problem, in vivo experimentation allowed testing to occur in the original organism or environment . To bridge the dichotomy of benefits associated with both methodologies, in situ experimentation allowed the controlled aspects of in vitro to become coalesced with the natural environmental compositions of in vivo experimentation . </P> <P> In conservation of genetic resources, "in situ conservation" (also "on - site conservation") is the process of protecting an endangered plant or animal species in its natural habitat, as opposed to ex situ conservation (also "off - site conservation"). </P> <P> In chemistry, in situ typically means "in the reaction mixture ." </P> <P> There are numerous situations in which chemical intermediates are synthesized in situ in various processes . This may be done because the species is unstable, and cannot be isolated, or simply out of convenience . Examples of the former include the Corey - Chaykovsky reagent and adrenochrome . </P>

What is the meaning of situ in chemistry