formation of 16 or 32 autospores, and after breaking down the mother-cell
envelope the cycle is repeated.
Similar are the cases with T. Sedova and B. Zakryś. Studying the
sporogenesis in the unicellular green alga Palmellococcus (Sedova,
1972) has observes a cell with three nuclei, which gives grounds to draw
a picture of asynchronous division, but she overlooks this fact without any
explanation. In Euglena cells (Zakryś 1980, 1983) has registered uneven
number of nuclei and a generation with uneven number of daughter “cells,
considered by him as” aberrative divisions with rudimentary character.
A great number of such cases can be given from the literature. That
demonstrates the enormous influence of the conception of synchronous
division on interpreting the results of this kind of studies.
Analyzing the results of the studies performed on unicellular green
algae of Scenedesmus and Chlorella genera (Nicolov, and Nicolov et al.,
1982—1997 a) made it possible to draw the following important
conclusions:
First. Nuclear division occurs asynchronously up to the formation of
“crucial” number of nuclei, and when the mother cells have formed the
corresponding cell coenobia they go on to division. At that always in one of
the nuclei, more advanced in its development than the others, the next
division is realized earlier.
Second. The formation of daughter cells (autospores) also occurs
asynchronously, by analogy with nuclear division.
Third. Observing two dividing nuclei in one cell (see Fig. 3–18 e)
cannot be considered proof of a synchronous process of division.
Reasonably is to suppose that these two nucleus are in different phases,
which cannot be recorded by a cytological picture fixing a given moment
statically. That can be consider time-coincidence caused by the dynamic
processes ensuring the rapid formation of numerous nuclei necessary for
obtaining a great amount of daughter cells (autospores).
Fourth. The presence of even number of nuclei (two, four, eight,
etc.) as well as obtaining such number of daughter cells in one
coenobium, which meets the basic requirement of the conception of
synchronous division, does not mean that nuclear and cellular
reproductions have occured synchronously. These cases can be consider
separate stages of one asynchronous process, where there are both even
and uneven number of nuclei and daughter cells (see Fig. 3–24).
The asynchronous nuclear and cell division poses a lot of questions.
Three of them deserve a special attention.
What kind of process is that realizing the asynchronous nuclear
reproduction, i.e. whether it is uniform, with equal periods of the individual
cycles or it is irregular?
On the basis of the essence of asynchrony as biological process one
can suppose its irregularity. Its realization is a function of combining many