Page 4 - lesson notes-Plant Growth& Movement

Geometric Growth- here initial growth is slow and increase rapidly thereafter. Every
cell divides. The daughter cells grow and divide and the granddaughter cells that

result into exponential growth.

Geometrical growth is common in unicellular organisms when growing in nutrient

rich medium.

Sigmoid growth curve consists of fast dividing exponential phase and stationary
phase. It is typical of most living organisms in their natural environment.

Exponential growth can be represented as follows-

rt
W =W e . W1 = final size, W0 = initial size, r = growth rate, t = time of growth and e is the
1
0
base of natural logarithms (2.71828).

Quantitative comparison between the growth of living system can be made by

1. Measurement and comparison of total growth per unit time is called the absolute rate.

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