Biology · Plant Growth and Development · NEET
No. Totipotency is the ability (the inbuilt power) of a plant cell to make a whole plant. Tissue culture is the technique (the method in the lab) that uses this power. So totipotency is the reason tissue culture works, not the method itself. This exact difference was tested in NEET 2024, where micropropagation and somatic hybridization were the wrong (technique) options and totipotency was correct.
Almost any living cell that has a complete nucleus (full set of genes) can, in the right conditions. The cell must be alive and non-reproductive damaged. Dead cells like mature xylem vessels or cork cells cannot, because they have no living protoplast. NCERT says a whole plant can be regenerated from any part of a plant (called an explant).
Differentiation is a cell becoming a special, mature cell (like a root hair or a vessel). Totipotency is the reverse power — a specialised cell going back and making the whole plant again. In culture, a differentiated cell first dedifferentiates (regains division power) and then can express its totipotency to form a new plant.
Plant cells keep all their genes active-ready and can regain division power (dedifferentiate) easily. Most adult animal cells become fixed in their job and lose this power. For NEET, remember: totipotency is a hallmark (special mark) of plant cells.
When an explant is placed in nutrient medium with auxin and cytokinin, its cells divide and form a callus — an unorganised mass of undifferentiated cells. This callus can then be guided to form shoots and roots, giving a whole plant. So callus formation is the practical proof of totipotency. The next concept, callus and tissue culture, explains this step in detail.
The capacity to generate a whole plant from any cell of the plant is called
You are given a tissue with its potential for differentiation in an artificial culture. Which of the following pairs of hormones would you add to the medium to secure shoots as well as roots?
Try the real previous-year questions from this chapter — each with the answer and a full solution.
Totipotency is the capacity of a single plant cell or explant to grow into a complete whole plant under suitable conditions.
Scientists learned in the 1950s that whole plants could be regenerated from explants grown in sterile nutrient media, showing totipotency in practice.
Yes. Plants grown from one parent by tissue culture (using totipotency) are genetically identical copies called somaclones.
A carbon source like sucrose, plus inorganic salts, vitamins, amino acids and growth regulators such as auxins and cytokinins.
