Plants ) )

Bryophytes :
Bryophytes are all embryophytes ('land plants') that are non-vascular: they have tissues and enclosed reproductive systems, but they lack vascular tissue that circulates liquids. They neither have flowers nor produce seeds, reproducing via spores. The term bryophyte comes from Greek βρύον - bruon, "tree-moss, oyster-green" < βρύω - bruo, "to be full to bursting, to abound" + φυτόν - fyton "plant".The bryophytes do not form a monophyletic group but consist of three groups, the Marchantiophyta (liverworts), Anthocerotophyta (hornworts), and Bryophyta (mosses). Modern studies of the land plants generally show one of two patterns. In one of these patterns, the liverworts were the first to diverge, followed by the hornworts, while the mosses are the closest living relatives of the polysporangiates (which include the vascular plants). In the other pattern, the hornworts were the first to diverge, followed by the vascular plants, while the mosses are the closest living relatives of the liverworts. Originally the three groups were brought together as the three classes of division Bryophyta. However, since the three groups of bryophytes form a paraphyletic group, they now are placed in three separate divisions.
Pteridophytes :
The pteridophytes are vascular plants (plants with xylem and phloem) that neither flower nor produce seeds, hence they are called vascular cryptogams. Instead, they reproduce and disperse only via spores. They do not form a monophyletic group but consist of several groups, the Lycopodiophyta (club mosses, spike mosses, and quillworts), the Equisetophyta (horsetails), the Psilotophyta (whisk ferns), the Ophioglossophyta (adder's tongues and grape ferns), and the Pteridophyta (true ferns) and are monocots most of the time.In addition to these living groups of pteridophytes are several groups now extinct and known only from fossils. These groups include the Rhyniophyta, Zosterophyllophyta, Trimerophytophyta, and the progymnosperms.Modern studies of the land plants agree that all the pteridophytes share a single common ancestor. However, they are not a clade (monophyletic group) because the seed plants are also descended from within this group -- probably close relatives of the progymnosperms
Gymnosperms:
Gymnosperm (Gymnospermae) are a group of spermatophyte seed-bearing plants with ovules on the edge or blade of an open sporophyll, which are usually arranged in cone-like structures. The other major group of seed-bearing plants, the angiosperms, [from the Greek, 'angion' - container] have ovules enclosed in a carpel, a sporophyll with fused margins. A carpel consists of a stigma, style and the ovary. The term gymnosperm comes from the Greek word gumnospermos (γυμνόσπερμος), meaning "naked seeds" and referring to the unenclosed condition of the seeds, as when they are produced they are found naked on the scales of a cone or similar structure. There are between 700 and 900 species of Gymnosperm. It is widely accepted [1] that the gymnosperms originated in the late Carboniferous period of the Paleozoic era within the Phanerozoic eon. Early characteristics of seed plants were evident in fossil progymnosperms of the late Devonian period around 380 million years ago. Often gymnosperms are used for economical uses and as folk medicines. Some common uses for them are soap, varnish, lumber, paint, edible plants, and perfumes. Conifers are by far the most abundant gymnosperms with around 600 species. Cycads are the next most abundant group with about 130 species. Approximately 75 - 80 species of Gnetales exist and only one species of Ginkgo remains today.
Angiosperms :
The flowering plants or angiosperms (Angiospermae or Magnoliophyta) are the most widespread group of land plants. The flowering plants and the gymnosperms are the only extant groups of seed plants. The flowering plants are distinguished from other seed plants by a series of apomorphies, or derived characteristics.
There are eight groups of living angiosperms:
• Amborella - a single species of shrub from New Caledonia
• Nymphaeales - about 80 species[15] - water lilies and Hydatellaceae
• Austrobaileyales - about 100 species[15] of woody plants from various parts of the world
• Chloranthales - several dozen species of aromatic plants with toothed leaves
• Ceratophyllum - about 6 species[15] of aquatic plants, perhaps most familiar as aquarium plants
• magnoliids - about 9,000 species,[15] characterized by trimerous flowers, pollen with one pore, and usually branching-veined leaves - for example magnolias, bay laurel, and black pepper
• eudicots - about 175,000 species,[15] characterized by 4- or 5- merous flowers, pollen with three pores, and usually branching-veined leaves - for example sunflowers, petunia, buttercup, apples and oaks
• monocots - about 70,000 species,[15] characterized by trimerous flowers, a single cotyledon, pollen with one pore, and usually parallel-veined leaves - for example grasses, orchids, and palms
The exact relationship between these eight groups is not yet clear, although it has been determined that the first three groups to diverge from the ancestral angiosperm were Amborellales, Nymphaeales, and Austrobaileyales, in that order.[16]