Fusiform initials form:

The cork cambium,cork and secondary cortex are collectively called

In dicot stem,secondary xylem lies towards the ...$A$... and secondary phloem lies towards the ...$B$.... Choose the correct combination of options for $A$ and $B$.

Some vascular bundles are described as open. This is because they:

Initiation of lateral roots and vascular cambium during secondary growth takes place in cells of:

Assertion : In woody stems,the amount of heart wood continues to increase year after year.
Reason : The cambial activity continues uninterrupted.