A fossilized stem of Dernbachia brasiliensis, a tree fern of the Permian (250-300 million years ago). Water-conducting xylem tissue is highlighted in blue. Disclaimer: AAAS and EurekAlert!

As water travels through the xylem in the stem and leaf, it is being replaced by water taken up by the roots. Temperature Increases An increase in temperature increases evaporation, so the rate of ...

A continuous column of water is therefore pulled up the stem in the transpiration stream by evaporation from the leaves. As water travels through the xylem in the stem and leaf, it is being ...

Vascular cambium produces xylem (wood) and phloem, and together with the cork cambium ... We combine lineage tracing and microscopy with molecular genetics to understand growth dynamics of the stem ...