Give one basic functional difference between phellogen and phelloderm.
$\Rightarrow$ vCork cambium is an active tissue while periderm is a permanent tissue. Phellogen is produced from cells of cortex. Sometimes formed from cells of pericycle. These cells are actively divided and produce phellem cells outside and cells of periderm inside. Hence periderm is produced from cork cambium.
In dicot stem, vascular bundles are
In old trees, the greater part of secondary xylem is dark brown due to the
Identify $X$ and $Y$ in figure
$X-Y$
Give differences: Heartwood and Sapwood
The intrafascicular cambium