Question

Read the following statements:
I. According to the Liebig’s law of minimum, the growth is regulated by the limited factors i.e., resources in scarcity and not by the resources in abundance.
II. Shelford’s law of tolerance states that, only the factors present in excess/abundance can affect the growth, development of an organism or rate of biological process.
III. Shelford’s law of tolerance states that, an organism's success is based on a complex set of conditions and that each organism has a certain minimum, maximum, and optimum levels of environmental factor or combination of factors that determine success.
The correct choice is:

• A. I and II are correct; III is incorrect
• B. I and III are correct; II is incorrect
• C. II is correct; I and III are incorrect
• D. III is correct; I and II are incorrect

Hint:

- Liebig: growth depends on the limiting factor (minimum).
- Shelford: success depends on tolerance range (min, max, optimum).

Answer 1

The Correct Option is B

Step 1: Liebig’s law of minimum (Statement I).
- It states that growth is limited by the scarcest resource (limiting factor). - Resources in abundance do not regulate growth, but those in short supply do. Hence, Statement I is correct.
Step 2: Shelford’s law of tolerance (Statement II).
- This law does not state only "excess factors". - It emphasizes that too little or too much of any factor can limit growth. Hence, Statement II is incorrect.
Step 3: Shelford’s law detailed (Statement III).
- Success of an organism depends on the tolerance range (minimum, maximum, optimum). - Correctly describes Shelford’s law. Hence, Statement III is correct.
Step 4: Match with options.
I and III are correct; II is incorrect → Option (B). Final Answer: \[ \boxed{\text{(B) I and III are correct; II is incorrect}} \]