Biology · Biotechnology and Its Applications · NEET
The meristem (apical and axillary) is the region of very actively dividing young cells at the tips. NCERT simply states this region is free of virus. The commonly taught reason is that the meristem cells divide so fast that the slower-moving virus cannot keep pace with them, and this tip region also lacks the mature vascular connections through which many viruses spread. For NEET you only need the NCERT fact: even in an infected plant, the apical and axillary meristem is virus-free.
The meristem (apical and axillary) is best suited. This is a direct NCERT exercise question. Reason: even if the rest of the plant is infected with a virus, the meristem is free of virus, so removing it and growing it in vitro gives virus-free plants.
It avoids the virus, it does not kill it. You are not treating the infected tissue. You are choosing the one part (the meristem) that the virus has not reached, and growing a whole new plant from that clean part using totipotency.
They are related but not the same. Micropropagation is producing thousands of genetically identical plants (somaclones) through tissue culture. Recovering healthy virus-free plants from diseased plants using the meristem is one important application of the same tissue-culture method. So meristem culture uses the micropropagation technique for a specific purpose: healthy plant recovery.
NCERT lists banana, sugarcane and potato. Scientists have succeeded in culturing the meristems of these plants to obtain virus-free stock. Remember them as B-S-P (Banana, Sugarcane, Potato).
Try the real previous-year questions from this chapter — each with the answer and a full solution.
The meristem is the region of actively dividing young cells at the plant tips (apical) and in leaf axils (axillary), and NCERT notes it stays free of virus even in an infected plant.
It is grown in vitro (in a test tube) under sterile conditions on a nutrient medium containing a carbon source like sucrose, inorganic salts, vitamins, amino acids and growth regulators such as auxins and cytokinins.
Yes. Since they are produced by tissue culture (micropropagation) from the parent plant's own meristem, they are genetically identical, called somaclones, but without the virus.
Crops like banana, sugarcane and potato are propagated vegetatively, so a virus in the mother plant passes to all offspring. Meristem culture breaks this chain and gives clean, healthy, high-yielding stock.
