  A hypothesis of singleness of the growth equation for biological objects on
different organizational levels and dimensional analysis are used in order to
substantiate Schmalhausen's model of ontogenetic growth (the mass of a growing
organism is a power function of time). It is stated that such a model is valid
only in the initial period of growth. For the whole period of growth, a
generalization of Schmalhausen's model is advanced; it provides the same
accuracy as previously known models of quantitative description of kinetic
curves. Within the scope of the developed model, a number of interesting
results related to an allometry and biological time are obtained.
