Vascular bundle is closed when

Options

A. xylem and phloem are present
B. xylem and phloem occur in separate bundles
C. vascular cambium is present between xylem and phloem
D. vascular cambium is not present.

Answer

D

Explanation

The vascular system consists of complex tissues, the phloem and the xylem. The xylem and phloem together constitute vascular bundles. In dicotyledonous stems, cambium is present between phloem and xylem. Such vascular bundles because of the presence of cambium possess the ability to form secondary sylem and phloem tissues, and hence are called open vascular bundles. In the monocotyledons, the vascular bundles have no cambium present in them, Hence, since they do not form secondary tissues they are referred to as closed.