During animal differentiation, holes and tubes are usually developed by cell movement and the plastic folding of whole tissues; but the rigid walls of plant cells makes such migrations all but impossible in morphogenesis.

Instead plants resort to selective senescence and death of cells (lysigeny) with or without cell separation (schizogeny) to generate complex shapes and channels.

The delicate structure of the lace plant leaf (pictured on the left) is made by a patterned senescence of cells early in leaf development.

The pipework represented by the cellular structure of wood (above right) is also generated by senescence, autolysis and elimination of the contents of xylem initials.