Stem and roots of cruciferae grow due to activity of

Food material stored in xylam parenchyma in the form of................

The meristematic tissue responsible for the cutting of vascular tissue $(xylem \;and \;phloem)$ is called

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

Identify the correct order of the components with reference to their arrangement from outer side to inner side in a woody dicot stem.

$I.$ Secondary cortex

$II.$ Autumn wood

$III.$ Secondary phloem

$IV.$ Phellem

Describe contribution of cork cambium in secondary growth.