The cell wall is impermeable to water and the deposition of suberin is also found in:

In woody dicotyledons,the arrangement of vessels is either diffuse porous or ring porous. Based on these data,which one of the following statements is correct?

Bottle cork is obtained from .........

The cork cambium,cork and secondary cortex are collectively called

$A$: Bark is all the tissues outside the vascular cambium.
$R$: Bark is formed due to the activity of phellogen only.

Increase in the girth of plant (organ) takes place by