Write an essay on pteridophytes plants

But the idea of the relative position of this group Pteridophyta within the Plant Kingdom has greatly changed in recent days. Examples include mosses, liverworts, hornworts of bryophytes while spikemosses, clubmosses, ferns, quillworts are examples of pteridophytes.

In fact, they can be considered as the first terrestrial vascular plants, showing the presence of the vascular tissue, xylem, and phloem.

pteridophytes habitat

Multicellular sporangia. There are tiny floating ferns used as "green fertilizer" in rice paddies because they partner with bacteria that pull nitrogen from the air and "fix" it in chemical compounds that other plants can use.

Write an essay on pteridophytes plants

There are about eleven thousand different species of pteridophytes, making them the most diverse land plants after the flowering plants angiosperms. Spores that are wind-borne to shady, moist habitats germinate and yield multicellular, but microscopic, gametophytes, the sexual stage of the life cycle. They are the vascular plants those having xylem and phloem tissues that reproduce by releasing spores rather than seeds, and they include the highly diverse true ferns and other graceful, primarily forest-dwelling plants. Although most pteridophytes are homosporous produce spores that are all the same size , a few groups are heterosporous with large megaspores and small microspores. Some of the species belonging to this division have small leaves called as the microphylls. Features of Pteridophytes Pteridophytes display differentiation. Before there were seed plants, there were pteridophytes such as large, treelike up to Their other common characteristics include vascular plant apomorphies e. The root system is always adventitious. Pteridophytes may represent the closest living relatives sister group to the seed plants. Gametophytes of bryophytes are always autotrophic and macroscopic; while in pteridophytes, gametophytes are saprophytic or extremely reduced microscopic structures. Studies have revealed that about 10 percent of the moisture found in the atmosphere is released by plants through transpiration. They are the megaspores and the microspores. Although frequently bisexual hermaphroditic , in most cases the sperm produced by a gametophyte cannot successfully fertilize its own eggs and must swim to archegonia on neighboring, genetically different gametophytes. Generally, the gametophytes require damp and cool places to grow, due to their dependence on water.

These gametophytes are free-living, multicellular and photosynthetic. For Example Fern plants.

pteridophyta diagram

The root system is always adventitious. The contrasting colors of the vascular tissue in the stems and leaf bases of these plants create complex and pleasing designs.

Tippo suggested that the Plant Kingdom be divided into two subkingdoms Thallophyta and Embryophyta and the latter be divided into two phyla—Bryophyta and Trachaeophyta. The plant body can be divided into a true root, stem, and leaves. The stem is either underground or aerial.

Phylogenetic analysis of green plant rbcL sequences.

pteridophytes definition biology

But, this is too vast a group to be considered as a single division as a vast majority of the modern plants are included here.

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Essay on Pteridophyta