Question

Match List-I with List-II:

Choose the correct answer from the options given below:

• (A) - (I), (B) - (II), (C) - (III), (D) - (IV)
• (A) - (IV), (B) - (III), (C) - (II), (D) - (I)
• (A) - (II), (B) - (I), (C) - (IV), (D) - (III)
• (A) - (III), (B) - (IV), (C) - (I), (D) - (II)

Hint:

To remember hormonal functions:
Gibberellins = Germination.
Auxins (IAA) = Apical elongation.
Cytokinins (BAP) = Cell division.
Abscisic acid (ABA) = Arrests germination (prevents vivipary).

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
Plant hormones (phytohormones) are signal molecules produced within the plant that regulate cellular processes, development, and environmental responses.
Each class of phytohormone exerts distinct, sometimes overlapping, physiological effects depending on the tissue type and developmental stage.

Step 2: Detailed Explanation:
Let us correlate the plant hormones with their corresponding physiological responses:
1. Gibberellins (A): Gibberellins play a critical role in breaking seed dormancy and promoting seed germination.
Upon seed imbibition of water, the embryo releases gibberellins, which diffuse to the aleurone layer to induce the synthesis of hydrolytic enzymes like \( \alpha \)-amylase. These enzymes break down stored starch to nourish the growing embryo.
Thus, (A) matches with (IV).
2. Indole-3-acetic acid (B): Indole-3-acetic acid (IAA) is the primary naturally occurring auxin.
It is synthesized in apical meristems and young leaves, promoting cell elongation through the acid growth hypothesis, which activates expansins to loosen the cell wall.
Thus, (B) matches with (III).
3. 6-Benzylaminopurine (C): 6-Benzylaminopurine is a synthetic cytokinin.
Cytokinins promote cell division (cytokinesis) and are used in tissue culture to induce shoot differentiation.
Thus, (C) matches with (II).
4. Abscisic acid (D): Abscisic acid (ABA) is a stress hormone that maintains seed dormancy and prevents vivipary (the premature germination of seeds while still attached to the maternal plant).
Mutants deficient in ABA synthesis often display vivipary.
Thus, (D) matches with (I).

Step 3: Final Answer:
The matching pairs are (A)-(IV), (B)-(III), (C)-(II), and (D)-(I), which corresponds to option (B).