Arithmetic Growth and Geometric Growth. - Practice Questions & MCQ

• The increased growth per unit time is termed as growth rate.
• It can be expressed mathematically.
• An organism or a part of the organism can produce more cells in a variety of ways.
• The growth rate shows an increase that may be arithmetic or geometric.

Arithmetic Growth:

• In arithmetic growth, following mitotic cell division, only one daughter cell continues to divide while the other differentiates and matures.
• On plotting the length of the organ against time, a linear curve is obtained.
• Mathematically, it is expressed as:

• The linear curve obtained is as follows:

Geometric Growth:

• In most systems, initial Growth is slow and is referred to as the lag phase.
• Then, it increases rapidly at an exponential rate referred to as log phase or exponential phase.
• The growth of plants slows down in cases of limited nutrient supply and results in the stationary phase. 
• When we plot the growth against time, it results in S-Curve or Sigmoid Curve.

• The sigmoid curve is the characteristic of living organisms growing in the natural environment and is typical for all cells, tissues and organs. 
• The exponential growth in expressed as:

• r is the relative growth rate and is also a measure of the ability of the plant to produce new plant material, referred to as efficiency index. 
• Hence, the final size of W₁ depends on the initial size, W₀.