Cell-wall Formation

Abstract

A CHARACTERISTIC difference between the processes of cell-wall formation in plants and animals has long been recognised. In the tissues of higher plants a new cell-wall is generally laid down on the nuclear spindle and then spreads peripherally until it cuts the cell into two. The cell-wall may thus be said to be endogenous in its origin. It is also generally believed that this plate on the spindle is first formed by the coalescence of a row of granules, afterwards splitting into two layers which secrete the primary wall between them. In animal cells, on the other hand, the characteristic method of division is by constrictions or furrows beginning at the periphery and proceeding inwards. The same is true of many Thallophytes.