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Organisms and Populations — BIOLOGY STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceBIOLOGYOrganisms and Populations5 Marks
Question
  1. Write an equation for Verhaulst-Pearl Logistic Growth, where.
N - Population density at a timet E.

r - Intrinsic rate of natural increase.

K - Carrying Capacity.
  1. Draw a graph for a population whose population density has reached the carrying capacity.
  2. Why is this logistic growth model considered a more realistic one for most animal populations?
  3. Draw a growth curve where resources are not limiting to growth of a population.
✓

Answer

  1. $\text{dN/dt}=\Big(\frac{\text{K}-\text{N}}{\text{K}}\Big)$

  3. This growth model is more realistic in nature, because, no population can sustain the exponential growth indefinitely, as there will be competition for basic needs.

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