They have homologous chloroplasts. Similar to land plants, they contain chlorophyll b and beta carotene as accessory pigments and thylakoids staked as grana. They also contain homologous cellulose cell walls and homologous peroxisomes, which contain anti photorespiration enzymes. Charophytes also have phragmoplasts that occur during cell divisions and homologous sperm, which are flagellated.
PTERIDOPHYTES
Vascular crytogams are the first vascular land plants. The main plant body is the sporophyte, which is differentieated into true roots, stems and leaves. Their xylem is lack of companion cells. The sporophyte reproduce by spores, borne in sporangia, sporangia are usually borne on fertile levaes called sporophylls. Pteridophytes are mostly homosporois, but some are heterosporous with microspores and megaspores.
BRYOPHYTES
Bryophytes are simple, green, land plants. Unlike higher plants such as ferns and flowers, they lack specialized woody water conducting vessels. Their relatively delicate, nonvascular structure limits the size to which they can grow. Bryophtes are nonvascular terrestrial plants that first emerged about 420 million years ago. They form the nonmonophyletic grouping Bryophyta and include mosses, liverworts, and hornworts.
GYMNOSPERMS
Gymnosperms are naked seeded spermatophytes, originated 350 millions years ago. Most of them have become extinct and some are represented by a few living species called living fossils. The main plant body is the diploid sporophyte, which is woody and perennial and differentiated into root, stem and leaves.
ANGIOSPERMS
Angiosperms are vascular plants and they have seeds like the gymnosperms. They are so advanced because of their ability to have flowers. The main advantage of the flower is to protect the plant's seed. Unlike gymnosperms, whose seeds are exposed to weather, animals, people, angiosperms have their seeds surrounded by flowers, which can offer incredible protection. Many angiosperms have an inner layer that surrounds the seed, storing food and protecting the seen from harm, and an outer layer that protects the seed from the elements or animal attacks.
REFERENCES
google images
http://www.preservearticles.com/201101102902/gymnosperms.html
http://bryophytes.plant.siu.edu/bryojustified.html
http://www.wisegeek.com/what-are-angiosperms.htm
http://www.preservearticles.com/201101102901/pteridophytes.html
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