A longitudinal section of G. angustifolia
shows long and short parenchyma cells (Fig.
3a). In cross section one can see that the
parenchyma tissue is formed by both long cells
and short cells that become lignified after the
early stages of the shoot’s growth. The long
cells usually have thicker walls, while the short
cells are small and cubic in shape. They are
characterized by denser cytoplasm and thin
walls because they do not lignify with age like
the long cells. Simple pits are located in the
longitudinal walls connecting the parenchyma
cells amongst themselves. The function of
these two types of parenchyma cells remains
unknown (Grosser & Liese, 1971).