|MadSci Network: Botany|
Pith is a kind of "ground tissue" in the center of the stem or root. It consists primarily of parenchyma, a sort of thin-walled cell in plant, although the parenchyma in pith often has lignified secondary wall. In many stems the central part of the pith is destroyed during growth, but the pith in nodes will be retained. It is still not quite clear if the pith in root and stem is the same.
The pith cells in the stem often have chloroplasts. Basically, the function of pith is to store nutrition, at the same time, its parechymatous quality enables it to take responsbility of transporting nutrients to outer tissues in the plant.
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