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Organisms and Populations — BIOLOGY STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceBIOLOGYOrganisms and Populations5 Marks
Question
Comment on the growth curve given below.

✓

Answer

A population growing in a habitat with limited resources show initially a lag phase, followed by phases of acceleration and deceleration and finally an asymptote, when the population density reaches the carrying capacity. A’ plot of N in relation to time (t) results in a sigmoid curve. This type of population growth is called Verhulst-Pearl Logistic Growth and is described by the following equation:
$\frac{\text{dN}}{\text{dt}}=\text{rN}\Big(\frac{\text{K}-\text{N}}{\text{K}}\Big)\\\ \ \\\frac{\text{dN}}{\text{dt}}=\text{rN}\Big(1-\frac{\text{N}}{\text{K}}\Big)$
$\Big(1-\frac{\text{N}}{\text{K}}\Big)$ Environmental resistance.

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