Question

Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R.
Assertion A: The logistic growth model of populations is considered more realistic than the exponential growth model.
Reason R: Resources are finite.
In the light of the above statements, choose the most appropriate answer from the options given below:

• A. A is not correct but R is correct
• B. Both A and R are correct and R is the correct explanation of A
• C. Both A and R are correct but R is not the correct explanation of A
• D. A is correct but R is not correct

Hint:

Verhulst-Pearl Logistic Growth is mathematically expressed as: \(\frac{dN}{dt} = rN \left(\frac{K - N}{K}\right)\). When \(N = K\), population growth stops, representing the maximum population size that the environment can support.

Answer 1

The Correct Option is B

Concept:

• Exponential growth: Assumes unlimited resources, resulting in a J-shaped curve. This rarely occurs in nature.

• Logistic growth: Assumes limited resources, resulting in a Sigmoid (S-shaped) curve.

• The population size levels off as it reaches the carrying capacity (\(K\)) of the habitat.

Step 1: Evaluate the truth of the Assertion and Reason
Assertion A is true: The logistic growth model accounts for limiting factors, making it highly realistic.
Reason R is true: Habitats have a finite amount of resources (food, space, nesting sites).

Step 2: Check if R is the correct explanation of A
The logistic growth model is considered more realistic (Assertion) precisely because resources are limited and finite (Reason) in any natural habitat.
Thus, R is the correct explanation of A.