Name the population growth pattern the equation
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

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 rN
dt
dN
represents. What does ‘‘r’’ represent in the equation ? Write its
importance in population growth. 

• Exponential Growth − When the resources are unlimited, population tends to grow in an exponential pattern.

  • If the population size is N and the birth and death rates (not per capita) are b and d respectively, then increase or decrease in N at t (time period) is given by,

dN /dt = (b − d) × N

If (b − d) = r, then

dN/ dt = rN

r is the “intrinsic rate of natural increase”.

 The 'r' means intrinsic rate of natural increase. It is a measure of the instantaneous rate of change of population size.
Increase in value of r (when the value of r is positive) indicates that the population size of a species has increased during the particular period. Decrease in value of r (when the value of r is negative) indicates that the population size of a species has decreased during the particular period.