Class 11 Biology Chapter 13 Plant Growth and Development – Revision Notes

Quick revision notes for Class 11 Biology Chapter 13 (Plant Growth and Development). These Class 11 Biology Chapter 13 notes are ideal for quick revision just before exams.

Growth Characteristics

• Indeterminate, open growth; sigmoid curve: lag, log, stationary phases.
• Phases: meristematic, elongation, maturation.

Plant Hormones

• Auxin: elongation, apical dominance.
• Gibberellin: stem elongation, germination.
• Cytokinin: cell division, delays senescence.
• Ethylene: fruit ripening (only gaseous hormone).
• ABA: stress hormone, dormancy, stomatal closure.

Photoperiodism & Vernalisation

• Flowering response to day/night length (short-day, long-day, day-neutral).
• Vernalisation: flowering promoted by cold exposure.

One-Line Summary

Plant growth is indeterminate and follows a sigmoid pattern, regulated by five major phytohormones (auxin, gibberellin, cytokinin, ethylene, ABA) along with photoperiod and temperature cues controlling flowering.

Written by Satish

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