Give an account on vascular bundle of dicot stem.
a. A type of bundle, the xylem and phloem are bundled together and lie on the same radius are called .
b. A type of bundles, the xylem is in the centre, and the phloem is on the periphery are called .
c. Protoxylem lies towards the centre, and the metaxylem lies towards the periphery. This condition is called .
d. The presence of cambium, the vascular bundles of dicot stems, are .