MCQ
Some vascular bundles are described as open because these:
  • A
    Are surrounded by pericycle but no endodermis
  • B
    Are not surrounded by pericycle
  • C
    Possess conjunctive tissue between xylem and phloem
  • D
    Are capable of producing secondary xylem and phloem

Answer

D. Are capable of producing secondary xylem and phloem
Explanation:
The vascular bundle which has cambium are called open vascular bundles. They are found in dicot stem and root. Open vascular bundles contain an interfascicular cambium. Phloem and xylem are not in direct contact with each other in that case. Secondary growth occurs in the cambial tissues. So, open bundles produce secondary xylem and phloem in between the primary phloem and xylem. These are either collateral or bicollateral.

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