Which of the following meristems is responsible for extrastelar secondary growth in dicotyledonous stem? (a) Interfascicular cambium (b) Intercalary meristem (c) Phellogen (d) Intrafascicular cambium
Option C Extrastelar secondary growth means growth in the cortical region, external to stele. For extrastelar secondary growth the cork cambium or phellogen develops in the region outside the vascular tissue. This gives rise to cork or phellem and secondary cortex or phelloderm. All the three layers (i.e, cork, cork cambium and secondary cortex) together constitute periderm. Fascicular and interfascicular cambuim occurs in the stelar regions.
