Question

What is the site of perception of photoperiod necessary for induction of flowering in plants?

• A. Lateral buds
• B. Pulvinus
• C. Shoot apex
• D. Leaves

Answer 1

The Correct Option is D

The question asks about the site of perception of photoperiod, which is essential for the induction of flowering in plants. The correct answer among the given options is Leaves.

Here's the explanation:

1. Concept of Photoperiodism: Photoperiodism is the physiological reaction of organisms to the length of day or night. It is a critical factor in determining the flowering time of plants.
2. Role of Leaves: In plants, the leaves recognize the length of daylight and darkness, which is crucial to initiating the flowering process. The perception of the photoperiod occurs in the leaves, where they detect changes in the duration of light and dark periods.
3. Induction of Flowering: Upon perceiving the appropriate photoperiod, the leaves send floral stimuli, also known as "florigen", to the shoot apex to initiate flowering.
4. Ruling Out Other Options:
   • Lateral buds: These are potential sites for new shoot growth but are not involved in the perception of photoperiod.
   • Pulvinus: This is a swollen part at the base of the leaf stalk that facilitates leaf movements but does not perceive photoperiods.
   • Shoot apex: While it is involved in flowering after receiving signals, it is not directly responsible for photoperiod perception.

Conclusion: Therefore, the leaves are the correct site for the perception of photoperiod necessary for the induction of flowering in plants.