Define bark.

The waxy substance associated with the cell walls of cork cells that makes them impervious to water is:

The $phellogen$ (cork cambium) develops from $...................$.

Statement-$1$: Heartwood is more durable and resistant to the attacks of microorganisms and insects compared to sapwood.
Statement-$2$: Heartwood contains organic compounds like oils,aromatic substances,gums,resins,tannins,and phenols.

Besides phellem and phellogen,the root periderm comprises of:

Other names of secondary cortex,cork cambium and cork are