19.What is the nature of wood? A. Primary xylem B. Secondary xylem C. Parenchyma D. Sclerenchyma
Option B The vascular cambium undergoes anticlinal divisions of form secondary xylem in the front and secondary phloem at the back. The elements of secondary xylem constitute wood. It consists largely of dead cells involved in the transport of water and minerals as well as support. An active wood contains water and stores food substances and is called sapwood. With the advance in age, the central axis of secondary xylem becomes inactive, losing water and stored food material. This is called as heartwood.
