Introduction. Development of the methodological base, disputes, conclusions.- Successes of the pulse amplitude modulated fluorescence application: Fluorescence spectroscopy in amino acid analysis.- Theory of energetic bases of the green cells resistance to abiotic environmental factors.- Methodological approaches in our experimental work: The Main Law of Light Absorption by a Substance.- Correctness and Accuracy of Spectrophotometric Data.- Basis of Derivative Spectrophotometry.- Application of the... Mehr