Tracheids are the water-conducting and mechanical supporting cells of gymnosperms; water is transported longitudinally through endplates and laterally through pits (a). Angiosperm vessels function primarily to transport water and are individually shorter than tracheids (b).

Xylem transports and stores water and water-soluble nutrients in vascular plants. Phloem is responsible for transporting sugars, proteins, and other organic molecules in plants.

Plants have tissues to transport water, nutrients and minerals. Xylem transports water and mineral salts from the roots up to other parts of the plant, while phloem transports sucrose and amino acids between the leaves and other parts of the plant.

The phloem carries important sugars, organic compounds, and minerals around a plant. Sap within the phloem simply travels by diffusion between cells and works its way from leaves down to the roots with help from gravity. The phloem is made from cells called ‘sieve-tube members’ and ‘companion cells’.

The main function of the phloem is to transport nutrients from the source where they are produced (e.g. the leaves through photosynthesis) to the sink (e.g. flowers and fruits) where they are used.

Tracheids serve for support and for upward conduction of water and dissolved minerals in all vascular plants and are the only such elements in conifers and ferns.

The most common patterns are annular, spiral, scalariform, reticulate, and pitted. When viewed from the top, the cells appear angular and polygonal. Tracheids have pits, which are concave depressions on the cell wall.

A tracheid is a long, lignified cell in the xylem of vascular plants. When mature, tracheids do not have a protoplast. The main functions are to transport water and inorganic salts, and to provide structural support for trees.