Histomers

HISTOMERS, a term introduced by M. Heidenhain for designating various, capable of reproduction (through division, fission, budding) microscopic structural formations of the organism when compared with more complex morphological formations (histosystems). Thus, the nucleus, centrosome, chloroplasts and other, capable of reproduction intracellular organelles are histomers in relation to the cell. In turn, the cell is a histomer in relation to the organ or tissue into which it enters. Thus, histomers can be of different orders, with histomers of higher order at the same time being histosystems in relation to the histomers of lower order constituting them. To histomers of the lowest order belong centrioles, chromioles, mitochondria and other smallest microscopic inclusions of protoplasm, capable of reproduction. Beyond these, distinguishable by us histomers of lower order, in the opinion of Heidenhain, stand microscopic particles of protoplasm, protomers, which are the last in this series of living, capable of reproduction units of organic matter.