What is Dedifferentiation? Interfascicular Cambium Example
Biology · Plant Growth and Development · NEET
Dedifferentiation is when a living, fully mature plant cell that had lost the power to divide gets that power back and becomes meristematic again. The classic NCERT example is the interfascicular cambium and cork cambium forming from fully developed parenchyma cells. Memory hook: "DE = un-do" — a done cell un-does its retirement and starts dividing once more.
Dedifferentiation is the middle step: mature parenchyma cells regain dividing power to become interfascicular cambium, then redifferentiate into permanent tissues.
Your doubts, answered
What exactly is dedifferentiation in simple words?
A mature plant cell (like parenchyma) had stopped dividing after it matured. Under certain conditions it becomes able to divide again. Getting back this dividing power is dedifferentiation. The cell turns meristematic again.
Why is the interfascicular cambium a dedifferentiation example?
During secondary growth, fully developed parenchyma cells of the medullary rays (between the vascular bundles) start dividing again and form a new meristem called interfascicular cambium. Since mature, non-dividing cells regained dividing power, this is dedifferentiation. Cork cambium (phellogen) from parenchyma is the same kind of example. This is the exact NCERT line, so NEET asks it directly.
How is dedifferentiation different from differentiation?
They move in opposite directions. Differentiation = meristematic cell matures into a permanent cell and loses dividing power. Dedifferentiation = a mature cell regains dividing power and becomes meristematic. So differentiation is 'settling down', dedifferentiation is 'un-settling'.
Is dedifferentiation the same as callus formation in tissue culture?
Yes, callus formation is a dedifferentiation example. When leaf mesophyll cells (mature, non-dividing) are put in a culture medium, they start dividing again to form a callus, a mass of dividing unspecialised cells. NEET 2023 asked exactly this.
What happens to dedifferentiated cells after they divide?
They do not stay dividing forever. The new cells they produce again lose the power to divide and mature to do a specific job. That maturing-again step is called redifferentiation. So the order is differentiation, then dedifferentiation, then redifferentiation.
⚠️ The NEET trap ✗ Formation of interfascicular cambium from parenchyma is called redifferentiation because a new tissue is formed. ✓ It is dedifferentiation. Mature parenchyma cells regaining the power to divide (becoming meristem) is dedifferentiation. Redifferentiation is the opposite: dedifferentiated cells maturing back into permanent cells. 🧠 Ask: did a mature cell START dividing (dedifferentiation) or STOP dividing to mature (differentiation/redifferentiation)? Interfascicular cambium = cells START dividing = dedifferentiation.
Real NEET questions
NEET 2024
Formation of interfascicular cambium from fully developed parenchyma cells is an example for
A · Redifferentiation
B · Dedifferentiation ✓
C · Maturation
D · Differentiation
Solution: Living differentiated cells that had lost the power to divide can regain it under certain conditions; this is dedifferentiation. Interfascicular cambium and cork cambium forming from fully differentiated parenchyma is the textbook example. Differentiation and redifferentiation are maturation (opposite direction), and maturation itself is not the regaining of dividing power.
NEET 2023
In tissue experiments, leaf mesophyll cells are put in a culture medium to form callus. This phenomenon may be called as:
A · Differentiation
B · Dedifferentiation ✓
C · Development
D · Senescence
Solution: Mature leaf mesophyll cells are differentiated cells that had lost the power to divide. When cultured to form a callus (a mass of dividing unspecialised cells) they regain dividing power, which is dedifferentiation. Differentiation is the opposite (maturation), while development and senescence are unrelated to regaining division.
NEET 2025
Read the statements: A. Parthenocarpy can be induced by auxins. B. Plant growth regulators can be involved in promotion as well as inhibition of growth. C. Dedifferentiation is a pre-requisite for re-differentiation. D. Abscisic acid is a plant growth promoter. E. Apical dominance promotes the growth of lateral buds. Choose the option with all correct statements.
A · A, D, E only
B · B, D, E only
C · A, B, C only ✓
D · A, C, E only
Solution: A, B and C are correct. C is true because a cell must first dedifferentiate (regain dividing power) before it can redifferentiate (mature again), so dedifferentiation is a prerequisite for redifferentiation. D is wrong (ABA is an inhibitor) and E is wrong (apical dominance inhibits lateral buds).
Solved Plant Growth and Development NEET PYQs
Try the real previous-year questions from this chapter — each with the answer and a full solution.
Dedifferentiation is the phenomenon in which living, fully differentiated (mature) cells that have lost the capacity to divide regain the capacity of division under certain conditions and become meristematic again.
Give two NCERT examples of dedifferentiation.
Formation of interfascicular cambium and cork cambium (phellogen) from fully developed parenchyma cells. Callus formation from mature cells in tissue culture is also an example.
Is dedifferentiation a prerequisite for redifferentiation?
Yes. A mature cell must first dedifferentiate (regain dividing power) before the new cells it makes can redifferentiate (lose dividing power and mature again). NEET 2025 tested this as a correct statement.
Which cells undergo dedifferentiation?
Living, mature, differentiated cells such as parenchyma (medullary ray parenchyma, cortical parenchyma, leaf mesophyll). Dead cells like mature tracheids cannot dedifferentiate.
Is dedifferentiation the same as plasticity?
No. Dedifferentiation is a mature cell regaining dividing power. Plasticity is a plant following different developmental pathways in response to environment (for example heterophylly). NEET 2026 used heterophylly as a plasticity example, not dedifferentiation.
