The Growth of Scenedesmus Acutus

Abstract

The population growth of S. acutus follows a logistic curve, except for a brief initial period. The equation for the curve is log (x + a) / (A[long dash]x)[long dash]K(t[long dash]t i), where x is the number of organisms at time t, a is the value of x at zero time, A is the final or limiting value of x, t 1 is the time when x = A/2, and K is a constant. This growth equation recognizes that there was a definite, though small, number of cells in the inoculum. The equation also affords a means for expressing the usual decline in the values of the growth constant during a growth cycle. If a is small in comparison with x, the value of K, the growth constant, will decrease only in the early part of the cycle. If a is large with respect to x, the growth constant will decrease more slowly and the growth curve will be asymmetrical.