In extrapolating from the properties of isolated cellular components to their functioning in a living cell, the idea of intracellular concentration enters critically. Whereas, in many practical situations the concept of concentration presents little difficulty, within the cell further considerations become relevant besides a simple arithmetic count of the number of molecules per unit volume. It is of course precisely this latter quantity that can, under favourable conditions, be measured. First, the possibility of intracellular heterogeneity, whether or not derived from physical compartmentation, should be considered. Also, from a metabolic point of view, the rate of turnover of a molecule, or part of a molecule, may be as important as its concentration. Further, the very low concentration of some substances in cells may itself pose problems of interpretation. Finally, because of evolution, the concentration of a cellular constituent will have a biological significance within the context of the cell, which is consistent with, but in addition to, strictly chemical considerations.
|Original language||English (US)|
|Number of pages||11|
|Journal||Bulletin of Molecular Biology and Medicine|
|State||Published - Jan 1 1976|
ASJC Scopus subject areas
- Clinical Biochemistry