Tracheophytes

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All tracheophytes, from the simplest psilopsids to the most complex angiosperms, have vascular systems for the internal distribution of water, minerals, and food. By contrast, the other grouping of terrestrial plants, bryophytes, do not have vascular systems but absorb water directly from the base on which they grow or from the air. There are two types of vascular tissue: Xylem conducts water from the ground to the stems and leaves, and phloem conducts the food that is produced in the leaves to the stems, roots, and storage and reproductive organs. Tracheophytes are the dominant land plants and include all trees and flowering plants.

Scientific classification: Psilopsids make up the division Psilophyta; lycopsids, the division Lycopodophyta; horsetails, the division Sphenophyta (or Equisetophyta); ferns, the division Filicinophyta (or Polypodophyta); cycads, the division Cycadophyta; ginkgos, the division Ginkgophyta; conifers, the division Coniferophyta; gnetophytes, the division Gnetophyta; and angiosperms, the division Angiospermophyta (or Magnoliophyta).

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