Unlike other gymnosperms they possess vessel elements in the xylem.

This suggests that the absence of vessel elements is a secondarily evolved character, not a primitive one.

Vessel elements are joined by perforations into vessels.

Tracheids, unlike vessel elements, do not have perforations.

Xylem vessels are a long straight chain made of tough long dead cells known as vessel elements.

The vessel elements are relatively small and usually 2-4-seriate; the medullary rays are fine and close together.

The other type of tracheary element, besides the tracheid, is the vessel element.

The vascular tissue contains vessel elements and in at least some taxa resembles that of the Gnetophyta.

Tracheids are one of two types of tracheary elements, vessel elements being the other.

Older morphological studies believed in a close relationship between the gnetophytes and the angiosperms, in particular based on vessel elements.

The roots of Marsilea and Regnellidium are noteworthy for containing vessel elements.

Plants have specialized tissue in the xylem vessel, that provides this function, see Vessel element.

Trochodendron and Tetracentron lack vessel elements in their wood, a quite unusual feature in angiosperms.

Trochodendron shares with Tetracentron the very unusual feature in angiosperms of lacking vessel elements in its wood.

(see Vessel element)

Unlike the water-conducting xylem vessel elements that are dead when mature, sieve elements are living cells.

Because tracheids have a much higher surface to volume ratio compared to vessel elements, they serve to hold water against gravity (by adhesion) when transpiration is not occurring.

Sap is the fluid transported in xylem cells (tracheids or vessel elements) or phloem sieve tube elements of a plant.

The gnetophytes differ from other gymnosperms (i.e. conifers, cycads, and ginkgos) in having vessel elements (which transport water within the plant) as found in flowering plants.

Lignin fills the spaces in the cell wall between cellulose, hemicellulose, and pectin components, especially in xylem tracheids, vessel elements and sclereid cells.

These include variations in the length and diameter of vessel elements in different parts of the plant; and the ability to reduce transpiration by closing off leaf stomata.

Tracheids and vessel elements are distinguished by their shape; vessel elements are shorter, and are connected together into long tubes that are called vessels.

In a work like "Spring Vase" (1996), on the other hand, the vessel element has become an almost hidden core, basically the structural support or internalized base for the sumptuous integument that sweeps around it.

The gnetifer hypothesis first emerged formally in the mid-twentieth century, when vessel elements in the gnetophytes were interpreted as being derived from tracheids with circular bordered pits, as in conifers.

The plant microfossil analysis recovered fragments of conifer tracheid and vessel elements with a ray of parenchyma cells, which corroborates the consumption of wood plants, pollen grains, spores, and fibers.