List of 28 pteridophytes with diagram biology discussion. Arrangement of the sori is quite varied and is often a key character is determining species. Extant pteridophytes are cosmopolitan but are much better represented in the humid tropics, with only a few families e. But trust me the first thing that you notice is the abundant foliage of fern plants. Today this subject is controversial, and scarcely considered in textbooks and journals of botany, in spite of its importance. Some 265300 genera and 10,90011,100 species recognized worldwide. However, the pteridophytes differ from mosses and seed plants in that both generations are independent and freeliving. There are mainly three types of steles in pteridophytes. A pteridophyte is a vascular plant with xylem and phloem that disperses spores.
As they produce neither flowers nor seeds, they are referred to as cryptogams. The dicksonia type of the basipetal marginal sorus may evolve from the state of superficial singlyarranged sporangia as seen in anogramma, from the cyathea type of the veinrelated superficial. Each sorus is covered by reniform to somewhat elongate indusium. Jan 23, 2017 occurence most of the pteridophytes are terrestrial and grow in moist and shady places while some flourish well in open, dry places especially in xeric conditions selaginella lepidophylla. There are two main categories of form and structure, one category comprises of megaphyllous types, in which the leaves are large in relation to the stem e. Firstly, pteridophytes are the vascular plants plants having xylem and phloem that reproduces via spores.
They are flowerless plants exhibiting an alternation of 2 distinct and dissimilar generations. They include some 650 taxa, at least 95% of the living species of tree ferns. Pteridophyta containing all the vascular plants that do not bear seeds. The pteridophytes ferns and fern allies pteridophytes are vascular plants and have leaves known as fronds tertium organum pdf portugues, roots and sometimes true stems. They formed the dominant part of the earths during palaeozoic and mesozoic periods on soral evolution. Classification of pteridophytes for a long time the division pteridophyta includedthe ferns, lycopods and horsetails.
Pteridophyta is the most highly evolved group among the cryptogams. Pteridophyte definition is any of a division pteridophyta of vascular plants such as a fern that have roots, stems, and leaves but lack flowers or seeds. The cryptogams include algae, fungi, lichen, bryophytes and pteridophytes. Multiple choice quiz on pteridophytes cryptogams are plants which do not produce flowers and fruits. Pteridophyta pteridophytes a division of the plant kingdom, comprising the vascular cryptogams. Some other uses are ferns provide natural vegetation thats important to both wildlife and birds. Pteridophytes are vascular plants and have leaves known as fronds, roots and sometimes true stems, and tree ferns have full trunks. The sexuality of pteridophytic gametophytes can be classified as follows. Occurrence and evolution of pteridophytes with its origin and economic importance in pteridophyta is a group of ancient plants. In some red algae, it may take the form of depression into the thallus.
Some pteridophytes are aquatic marselia, azolla and. Similar to the life cycle of seed plants, the pteridophytes also involves the alternation of generations in its life cycle. These ferns, in biological terms, are nothing but the pteridophytes, belonging to the division pteridophyta of the plant kingdom. In early ferns, and some living ones, sori occur on specialized, exceedingly unleaf. They have leaves, roots, stem and sometimes trunks also. O based on the position and distribution of phloem, two types of siphonostles reported among pteridophytes are a ectophloic siphonostele and b amphiphloic siphonostele. Instead, the water and minerals flow from the surface of the plant cell to cell in the plants body.
In many ferns a small leaf outgrowth called an indusium covers. There are also some purely aquatic ferns such as water fern or water velvet salvinia molesta and mosquito ferns azolla species. As the first examples of this type, the sori of selected hypolepidaceae and dennstaedtiaceae are treated in detail. A first checklist of the pteridophytes of togo west africa. The spore morphology of fern is unique among the species. All pteridophytes have a true alternation of generations, in which a dominant sporophyte generation produces spores through meiosis, and a freeliving gametophyte generation forms gametes egg and sperm by mitosis. Pteridophytes ferns and fern allies the plant list. General characteristics of pteridophytes key points easy.
It is ellipsoidal, monolete, and surface is rugose fig 6. Firstly all the botanists divided the plant kingdom into two large groups cryptogamia and phanerogamia, linnaeus 1754 used the term cryptogams for the first time for those plants which did not possess visible sex organs. If two types of spores are present in a single plant species then it is known as the heterosporous pteridophytes. Relations between submarginal and marginal sori in ferns jstor. Look at different types of reproduction look at the reproductive mechanisms in bryophytes, pteridophytes and gymnosperms summary types of reproduction asexual vegetative reproduction haploid spores n are produced in the sporophyte 2n by meiosis. Besides having various medicinal properties, the pteridophytes are also employed for a variety of commercial and environmental purposes. Pteridophyta pteridophytes a division of the plant kingdom, comprising the vascular cryptogams 1. Sori occur on the sporophyte generation, the sporangia within producing haploid meiospores. A read is counted each time someone views a publication summary such as the title, abstract, and list of authors, clicks on a figure, or views or downloads the fulltext. O based on the development, two types of sporangia are present in pteridophytes. When you think of forests and woods, you can picture trees, abundant lush green ferns, and other plants. Cormophyta is plant having real roots, stems, and leaves. The different species of selaginella are grown as the garden plants. Various animals use the fronds as food while birds and small creatures use the plants for cover.
Sporangia are mixed, stalked and devoid of paraphysis. Jan 11, 2018 therefore, the key difference between homosporous and heterosporous pteridophytes is that the homosporous pteridophytes produce one type of spores that are same in size whereas heterosporous pteridophytes produce two types of spores that are different in sizes. The heterosporous pteridophytes produce microspores and megaspores which germinate to give rise to male and female gametophytes respectively. They dont have conducting tissues for transportation of water and minerals. The true indusium is a separate and unique formation, the structural origins of which are not clear, that constitutes a more or less papery covering over the sorus. The first is a nonsexual, spore 2bearing, sporophyte 3 generation. Pteridophytes or pteridophyta, in the broad interpretation of the term, are vascular plants plants with xylem and phloem that reproduce and disperse via spores. In this study, the soral arrangement in certain pteridophytes are. According to the older botanists, the vascular bundle is the fundamental unit in the vascular system of pteridophytes and higher plants. Characteristics of pteridophyta pteridophyta is predicted as an oldest cormophyta. Pteridophytes tracheophytes without seeds lycopodium has only one type of each sorus is composed of many eggshaped sporangia and is covered by a circular.
The meristematic areathe region of new cell growththat produces them may continue its activities over a number of weeks, producing sporangia of all ages, older ones being pushed aside as new ones mature in their turn. In all pteridophytes the dominant plant is the sporophyte brown below with the gametophyte blue below shortlived. Pteridophytes biology encyclopedia plant, body joilethbwinmi. It is not accepted by most of the authors since in many pteridophytes there is stele without leaf gaps but having pith in the centre. Useful notes on the classification of pteridophytes. In 1880, the cryptogams of the plant kingdom were divided. The first is a nonsexual, sporebearing, sporophyte generation. Pteridophytes tracheophytes without seeds lycopodium has only one type of each sorus is composed of many eggshaped sporangia and is. We are perfectly safe in concluding that there has on the whole been.
Its means that the roots, stems, and leaves have vascular bundle, so pteridophyta also known as tracheophyta. In this article we will discuss about the classification of pteridophyta. Sporangia are located, for the most part, on the undersides of ordinary leaves in clusters called sori singular, sorus. It usually appears as a relatively large plant, with stems containing vascular tissue that conducts water and dissolved solutes through the. The pteridophytes are an economically important group of plants. In lichens and other fungi, the sorus is surrounded by an external layer. The megaspore and microspore germinate to give rise female and male gametophyte respectively. Some pteridophytes are aquatic marselia, azolla and some are epiphytes ophioglossum pendulum. Types of sorus depending upon the nature of the sorus and stage of sporangial development the ferns are divided as. This fern life cycle is representative of most pteridophytes.
Except pteridophytes all others are the lower cryptogams, as they do not possess true vascular cryptogams, as they do not possess true vascular tissue for conduction. Between onehalf and twothirds of the species of ferns have one or another of the following six soral arrangements. Relations between submarginal and marginal sori in ferns. Multiple choice quiz on pteridophytes biology multiple. With more than 10,000 known species of modern ferns, these plants display tremendous diversity in size, form and cultural needs. Read the introductory remarks and list of characteristics of the bryophytes p. Occurrence and evolution of pteridophytes biology boom. Fossil of pteridophyta found in the stone since carbon era past of 345 millions ago. I02 wardlaw and sharma sori in leptosporangiate ferns sori is a gradual.
Ferns stand out among garden regulars for their lack of flowers and seeds. Pteridophyta characteristics, life cycle, classification. In this lesson, well discover the characteristics, classification, and life cycle of the group pteridophyta, which includes plant species like. Experimental and analytical studies of pteridophytes. Unlike the ferns, which are a highly successful, flourishing group, the fern allies as we call the other pteridophytes are virtually living fossils.
Van tieghem and douliot 1886 interpreted the plant body of vascular plant in the different way. Pteridophyta teridafata os made from two greek roots that mean winged pteryz. Pteridophytes are seedless and they procreate through spores. Sporangium and sorus the number of spores produced per sporangium ranges from 16 or 32 in some pteridophytes to more a type of chemical process. Pteridophyta definition of pteridophyta by the free dictionary. Request pdf development of the sorus in tree ferns. Pteridophyte definition of pteridophyte by merriamwebster. Full text pdf online international interdisciplinary research journal. A widespread type of indusium among members of the family cyatheaceae is one shaped like a cup, which arises around the base of the sorus, often enclosing the sorus until the sporangia are mature e. Because pteridophytes produce neither flowers nor seeds, they are sometimes referred to as cryptogams, meaning that their means of reproduction is hidden.
This pdf version does not have an isbn or issn and is not therefore effectively published. Stelar theory, components of stele, different types of steles in plants, protostele. The origin of the sporophyte in land plants represents a fundamental phase in plant evolution. Even today, many tribal communities and rural populations are dependent heavily upon the natural resources obtained from the surrounding forest regions for treatment of various ailments and diseases. Before we look at the existing ferns and fern allies you should realize how important and common these plants once were. Occurence most of the pteridophytes are terrestrial and grow in moist and shady places while some flourish well in open, dry places especially in xeric conditions selaginella lepidophylla. Stelar evolution in pteridophytes ppt types of steles and its evolution in pteridophytes ppt what is stele. Ferns can be used to illustrate the life cycle stages common to all pteridophytes. Unlike the ferns, which are a highly successful, flourishing group, the fern allies as. A protostele has the vasculature xylem occupying the central region of the stele. Pteridophytes constitute a significant and important group in the plant kingdom.
In a siphonostele the vasculature is like a tube or siphon. Pteridophytes were dominant land plants during the carboniferous era and a major source of todays coal and oil. Most of their relatives have long since become extinct. Pteridophytes do not have seeds or flowers either, instead they also reproduce via spores. Before we look at the existing ferns and fern allies you should. Pteridophytes biology encyclopedia plant, body, different. The families share sporangia with an oblique annulus, initiation of the sporangia in a. The members of the class psilotopsida show close resemblance in fundamental characteristics to the silurian and devonian members of rhyniopsida e. On the basis of their anatomy jeffrey in 1902 divided the vascular plants into two types or stocks.
Therefore, the key difference between homosporous and heterosporous pteridophytes is that the homosporous pteridophytes produce one type of spores that are same in size whereas heterosporous pteridophytes produce two types of spores that are different in sizes. Botanically, they belong to the division of nonflowering plants known as pteridophyta. In many species, they are protected by an umbrellalike cover called the indusium. Reproduction in plants 19 february 2014 lesson description in this lesson, we.