Palingenesis

Palingenesis, such processes of individual development that can be considered as an inherited repetition of the developmental stages of more or less distant adult ancestors. The concept of P. was introduced by E. Haeckel simultaneously with the formulation of the biogenetic law (see) to denote the initial ('palingenetic') course of individual development (ontogeny), in which the embryo repeats the stages of the historical development (phylogeny) of a given form. As examples of those processes that, in Haeckel's opinion, have palingenetic significance in humans and higher vertebrates, he cites the formation of primary germ layers, the unsegmented laying down of the neural tube, the notochord, the disappearing gill slits and arches, the secondary kidneys, etc. Palingenetic traits, according to Haeckel, should be distinguished from later changes, or cenogeneses, introduced by the adaptation of the developing organism to its specific conditions of existence, by the shortening and simplification of development, etc.

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water exchange, acidosis); 2) biochemistry of avitaminoses (disorders of metabolism in various avitaminoses, the connection between vitamins and hormones); 3) biochemistry of muscular activity (it was established that the content of creatine in muscles increases during training), biochemistry of fatigue, clarification of the role of creatine-phosphoric acid in muscles, etc.; 4) biochemistry of the nervous system (the effect of starvation on proteolysis processes in the white and gray matter of the brain, creatine exchange processes in the brain). The works of P. in the field of biochemistry were awarded the V. I. Lenin Prize in 1929. The works of P. [over 70 (up to 1931)] were published mainly in 'Naukovyi Zapysky Ukrainskoho Biokhimichnoho Instytutu', in 'Biochemische Zeitschrift' and in 'Zeitschrift fur physiologische Chemie'. P. is the author of a widely distributed and many times reprinted textbook of physiological chemistry in Russian and Ukrainian (latest editions, Kharkov, 1931; Moscow, 1932) and the book 'Fundamentals of Nutrition' (3rd edition, Moscow, 1927). A summary of P.'s works on muscle biochemistry was published in 'Bulletin de la Societe de Chimie Biologique', 1931, No. 1.