Companion cells provide the energy for the sieve cells. The end walls of the sieve cells have pores through which sugar is transported from cell to cell.

Usually, the sieve-tubes of the phloem have been regarded as the channels of sugar transport, as micro-chemical observations, such as those of Prof. Mangham, seemed to show considerable quantities ...

Either way, they are never wanted. We’re talking about those annoying white strings on bananas, or more technically, “phloem ...

In a mature flowering plant or tree, most of the cells that make up the xylem are specialised cells called vessels.

The center of a tree or shrub stem (from roots to trunk, branches, and twigs) is woody, composed of xylem cells that conduct water from the roots to the upper parts of the tree. That woody section is ...