Hey NEET Aspirants ð
Do you ever feel confused between auxins, gibberellins, and cytokinins? Don’t worry — today we’ll make Plant Growth and Development super easy for you! ðŋ
This is one of those chapters where NEET loves to test your concepts + NCERT lines + logic.
So, let’s decode this chapter together in the simplest way possible — NEET-style!
---
ðŋ 1️⃣ What is Plant Growth?
Plant Growth = Increase in size, mass, and number of cells.
Simple na? But the magic is in how plants manage this growth. ðą
Unlike animals, plants grow throughout life because of special dividing tissues called Meristems.
These meristems keep producing new cells at specific locations.
ðŠī Three types of growth:
1. Primary Growth – increase in length (apical meristem)
2. Secondary Growth – increase in girth (lateral meristem)
3. Intercalary Growth – growth at nodes (seen in grasses)
---
ðą 2️⃣ Phases of Growth – The 3 Golden Steps
You must have seen the famous S-shaped growth curve in NCERT.
That curve shows the three important growth phases:
1. Lag Phase: Slow start (cells adjusting)
2. Log Phase: Rapid cell division (fastest growth)
3. Stationary Phase: Growth stops (no new cells divide)
ðĄ Trick to remember: “L-L-S = Lag, Log, Stationary.”
---
ðŋ 3️⃣ Factors Affecting Plant Growth
Plant growth depends on both internal (hormones) and external factors (light, temperature, nutrients).
ð External Factors:
Light = triggers photoperiodism ð
Temperature = affects enzyme activity
Water = helps cell elongation
ðŋ Internal Factors:
Hormones like Auxins, Cytokinins, Gibberellins, ABA, Ethylene control various processes.
---
ðą 4️⃣ Plant Growth Regulators (PGRs) – The Magic Molecules
Now, let’s make PGRs easy for NEET!
Hormone Function Fun Trick
Auxin Cell elongation, root formation “Auxin = Aage badho”
Gibberellin Stem elongation, seed germination “Grow taller with GA!”
Cytokinin Cell division, delay aging “Cytokinin = Cell ka mitra”
ABA (Abscisic Acid) Dormancy, stress response “ABA = Always Be Alert”
Ethylene Fruit ripening “Ethylene = Mithas wali gas” ð
ð§ NEET Tip: Auxin + Cytokinin = Tissue culture growth booster ðą
---
ðŋ 5️⃣ Photoperiodism and Vernalization – NCERT’s Favourites
These two topics give direct NEET questions every year.
ðļ Photoperiodism:
Response of plants to day/night length.
Short-day plants = Chrysanthemum
Long-day plants = Wheat
❄️ Vernalization:
Requirement of low temperature for flowering (example: Wheat, Barley).
Trick: “Vernalization = Winter wali preparation!”
---
ðą 6️⃣ Differentiation, Dedifferentiation, and Redifferentiation
Sounds tough? Let’s simplify:
Differentiation: Cells become special (like Xylem or Phloem).
Dedifferentiation: Specialized cell becomes dividing again (e.g., Cambium).
Redifferentiation: New dividing cell again becomes specialized.
ðŠī NEET Tip: Cambium is the best example of dedifferentiation!
---
ðŋ 7️⃣ NEET Question Trends
ð Commonly asked topics:
Growth curve
PGR full forms
Hormone functions
Photoperiodism examples
ðĄ Always mark NCERT tables — NEET loves direct lines like:
> “Ethylene is the only gaseous PGR.”
---
ðą 8️⃣ Quick Revision Summary
ð Growth = Permanent increase in size
ðŋ Phases = Lag → Log → Stationary
ð§ PGRs = Auxin, GA, Cytokinin, ABA, Ethylene
ðļ Photoperiodism = Day length response
❄️ Vernalization = Cold-induced flowering
Revise this summary 3–4 times before NEET and you’ll never forget it!
---
ðŋ Final Words by Botany Sir Himansu
> “If you understand plant hormones, you understand how life balances growth and rest.”
Stay consistent, stay curious, and let your concepts bloom ðą
Because every concept mastered is a step closer to NEET success.
---
ð Internal Links
Photosynthesis in Higher Plants – NEET 2025 Notes
Plant Growth Regulators Explained in 5 Minutes
Most Important Plant Physiology Questions for NEET
