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Q.
The cork cambium, cork and secondary cortex are collectively called :
AIPMTAIPMT 2011Anatomy of Flowering Plants
Solution:
The cell of the cork cambium divide to produce an outer corky tissue (cork or phellem) and an inner secondary cortex (phelloderm). Cork, cork cambium, and phelloderm together make up the periderm, an impermeable outer layer that protects the inner stem tissues if the outer tissues split as the stem girth increases with age.