[Method of recording the linear growth and cell mass displacement of multicellular animals and plants]. / Metodika registratsii lineinogo rosta i peremeshcheniia kletochnykh mass u mnogokletochnykh zhivotnykh i rastenii.

A photoelectrical method has been developed of registration of the linear growth and cell mass movements in the actively zones (growing tips, edges, etc). The device proposed transforms to electrical signals the changes in lighting of microscopic visual field caused by shifting the growing structures in the area restricted by the aperture of the ocular field diaphragm of the "cat-eye" type. By means of this technique, oscillograms of growth of the number of multicellular organisms have been obtained for the first time. In many cases (blastodisc edge and tail bud of the salmon Oncorhynchus gorbusha, mantle edge of Mytilus edulis, osculum edge of the sponge Tethya, apical area of brown alga Fucus and of red algae Polyides and Ahnfeltsia), a pulsatory character of growth (with periods of some minutes) were registered. A similar growth character was also confirmed for several species of Thecaphora hydroids. No pulsations was registered during the linear growth of a brown alga Laminaria (which contrary to Fucus is growing intercalarly), of Nitella (Charophyta) and of several high plants.

[Interaction radius of aggregating cells of freshwater sponge Ephydatia fluviatilis]. / O radiuse vzaimodeistviia agregiruiushchikh kletok presnovodnoi gubki Ephydatia fluviatilis.

A concept of the interaction radius of cells and cell aggregates is presented. Quantitative results of experimental investigations of these characteristics are presented by analyzing the motion of dissociated sponge cells. It is shown that association takes place mainly with cell aggregates of nearly the same size and an essential positive correlation between the interaction radius and their average diameter exists.

[Quantitative evaluation of periodicity of cell movement in the process of aggregation]. / Kolichestvennaia otsenka periodizma dvizhenii kletok v protsesse agregatsii

A method of quantitative estimation of quasiperiodic cell movements is considered which allows to approximate the process under study by the sum of trigonometric functions. The possibilities of the method are deomonstrated in the analysis of cell and aggregate movement during the development of a sponge Ephydatia fluviatilis from dissociated cells, taken as an example. The spectral composition of the movement of cell aggregates was found to change with time; the high frequencies disappear gradualy and the lower ones appear.