Question

Why are vascular bundles of a dicot stem called open?

Answer 1

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The vascular bundle of dicot stem is said to be open bundle since it possess a cambial strip between xylem and phloem.

Answer 2

Answer:

Vascular bundles of dicot stem are open, because of presence of cambium. Endarch is used when there is more than one strand of primary xylem in a stem or root and the xylem develops from the inside outwards towards the periphery, i.e., centrifugally. ... The stems of seed plants typically have endarch development.