Xylem and phloem are arranged in alternate radii inI.  Dicot leaf    II. Monocot leaf     III. Dicot root    IV. Monocot root

In leaves of monocots and dicots, the vascular bundles are conjoint collateral and closed. In roots, since xylem and phloem are present on separate radii, they are described as radial separate vascular bundles.