FORESTRY
PLANT AND WOOD ANATOMY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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is absent
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is completely secondary in origin
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does not form a continous ring
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originates from the tissue just above the phloem bundles
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Detailed explanation-1: -The vascular cambium in dicot stem is partly primary and partly secondary in origin. The intrafascicular cambium present inside the vascular bundle in the dicot stem is primary in origin while the interfascicular cambium formed from the cells of medullary rays is secondary in origin.
Detailed explanation-2: -The vascular cambium of trees is a secondary meristem and is responsible for the formation of the xylem and phloem.
Detailed explanation-3: -Secondary growth: It is defined as the increase in stem diameter due to the activity of the lateral meristem tissues. Let us now try to understand secondary growth in dicot plants: Secondary tissues in dicots are formed by lateral meristems which are of two types vascular cambium and cork cambium or phellogen.