At that time, what is now temperate europe and north america had climate conditions that favored yearround growth. Unlike the bryophytes, these plants are in the mainstream of land plant evolution and eventually gave rise to the seed plants. Although bryophytes and pteridophytes have gametes tha depend on water for fertilization, the emergence of conducting vessels in this last group facilitated life in a terrestrial environment. Phytochemical studies in pteridophytes growing in brazil. Read the introductory remarks and list of characteristics of the bryophytes p. Pteridophytes are a vascular plant and since bryophytes have no vascular system they are not capable to transport the water and nutrients from one part of the plant to another but pteridophytes can. Pteridophyta the word cryptogams means that the plant produce by spore and do not produce by seed. The pteridophytes are the successful colonisers on land habit.
Pteridophytes were dominant land plants during the carboniferous era and a major source of todays coal and oil. A concept based exclusive material pteridophytes, gymnosperms. What is one evolutionary advantage pteridophytes have over. Already on the origin of plant lineage, we still have no safe dating for the endosymbiotic event, i. Pteridophytes may represent the closest living relatives sister group to the seed plants.
Heterosporous megaspores important in species identifications and gametophyte development is endosporic. Pteridophytes or pteridophyta, in the broad interpretation of the term, are vascular plants plants with xylem and phloem that reproduce and disperse via spores. The invasion of pith occurs through the leaf gap or branch gap. Unlike the bryophytes, these plants are in the mainstream of land plant evolution and eventually gave rise to the seed. Characteristics of pteridophytes, morphology of pteridophytes, reproduction of pteridophytes, homosporous and heterosporous pteridophytes, megaspore and microspores, gametophytes of pteridophytes, fertilization, zygote and embryo of pteridophytes, life cycle. These keywords were added by machine and not by the authors. There are also some purely aquatic ferns such as water fern or water velvet salvinia molesta and mosquito ferns azolla species. Stelar theory, components of stele, different types of steles in plants, protostele.
Life forms of pteridophyta, their origin and evolution. Pteridophytes pteridophtyes are a phylum of plants. Life cycles of lycopodium, selaginella, equisetum, adiantum and marsilea. Extant pteridophytes are cosmopolitan but are much better represented in the humid tropics, with only a few families e. Pteridophytes or ferns first appeared in the fossil record more than 350 million years ago. It is speculated that life began in the oceans, and through millions of years of evolution, life slowly. Basic types of steles protostele central xylem, surrounding phloem.
The algae fungi bryophytes and pteridophytes are all cryptogams. A pteridophyte is a vascular plant with xylem and phloem that disperses spores. Various animals use the fronds as food while birds and small creatures use the plants for cover. The first vascular plants rapidly diversified to cover the earth.
The following separation of the main growth forms of pteridophyta is proposed. Furthermore, in hymenophyllous ferns, the sporophyte is. Ferns can be used to illustrate the life cycle stages common to all pteridophytes. Pteridophytes ferns and fern allies the plant list. Among green plant lineages, none are as speciesrich as vascular plants tracheophytes. Primitive siphonostele protostele with central pith.
The different species of selaginella are grown as the garden plants. 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. They had acquired certain characteristic features in the early geologic period that helped them to make their successful adaptation on land. The modern classification of pteridophytes have been suggested by many scientist according to the sporne1975 pteridophytes have been classified into six classes. Occurrence and evolution of pteridophytes with its origin and economic importance in pteridophyta is a group of ancient plants. Because pteridophytes produce neither flowers nor seeds, they are sometimes referred to as cryptogams, meaning that their means of reproduction is hidden. Jeffrey 1898, for the first time pointed out the stelar theory from the point of view of the phylogeny. Fronds in the largest species of ferns can reach some six metres in length. Systematic revision of pteris and ecology of ferns in. The molecular data indicate that lycopsids are monophyletic and are the earliest diverging group within the vascular land. The molecular data indicate that lycopsids are monophyletic and are the earliest diverging group within the vascular land plants. Each of these can be divided into life forms according to a series of morphological and other characters. The most characteristic feature of the pteridophytes is the presence. With the commencement of monsoon about mid june, the ferns and fernallies start growing vigourously and luxuriantly.
The pteridophytes are vascular cryptogams because they have well developed conducting system. Pteridophytes biology encyclopedia plant, body, different. Sumita, assistant professor, department of botany, pggc11, chandigarh. In addition, in pteridophytes, the gametophyte is often very thin and can be unistratose, especially at the margins yatskievych, 2003. They are psilopsida, psilotopsida, lycopsida, sphenopsida, pteropsida and progymnospermopsida. Besides having various medicinal properties, the pteridophytes are also employed for a variety of commercial and environmental purposes. Occurrence and evolution of pteridophytes biology boom. Sporophylls the leaves that bear sporangia are known as sporophylls. 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. This was around the time when coal was being formed. On the basis of ontogenetical studies, stomata in the pteridophytes may be broadly classified into.
As in seed plants, the greatest diversity of pteridophytes is found in the tropics, with only about six hundred species adapted for life in temperate climates. Pteridophytes fern and fern allies comprise more than 10,000 species throughout the world and are roughly distributed among 305 genera. It is a 4th year msci course, which is compulsory for students on the physics with astrophysics pathway and optional for other physics and physics and applied mathematics students. This pdf version does not have an isbn or issn and is not therefore effectively. According to this theory, the pith is formed as a result of the invasion of cortical parenchymatous cells into the stele. These are nonflowering, vascular and sporebearing plants, which include ferns and fernallies.
Most pteridophytes are terrestrial plants and thrive well in abundant moisture and shade while some flourish well in open, dry situations especially in xeric conditions. A newer method in which resins and polymers are directly injected into xylem tissue has proven. Pteridophyta characteristics, life cycle, classification. Jan 23, 2017 reproduction the sporophytes reproduce by spores which are produced within sporangia. Pteridophyte definition of pteridophyte by the free. Why are pteridophytes better adapted to dry land than bryophytes. In some pteridophytes the sporangia develop on stems i.
Summary and conclusions 83 chapter5 summary and conclusions pteridophytes are one of the most ancient plants. Pteridophytes do not have seeds or flowers either, instead they also reproduce via spores. Lloyd in flowering plants many of the diverse characteristics utilized in systematics to determine phylogenetic relationships represent direct adaptations to specific methods of pollination or reproduction. Seed plants include the angiosperms, the conifers, and a smaller assortment of other plants. Summary and conclusions pteridophytes are one of the most ancient plants. The origin and early evolution of plants on land pdf. A few pteridophytes are aquatic while still others are epiphytes. The pteridophytes are an economically important group of plants.
Online course stellar structure and evolution this course is taught as a halfmodule for phy412 astrophysics in the department of physics and astronomy at queens. Pteridophyta teridafata os made from two greek roots that mean winged pteryz. Morphological diversity and evolution of vegetative organs pteridophytes download pteridophytes or read online here in pdf or epub. Pteridophytes general characters ppt general characteristics, life cycle and reproduction of pteridophytes ppt what are pteridophytes.
This process is experimental and the keywords may be updated as the learning algorithm improves. The lower cryptogams algae, fungi and bryophytes have no conducting system. Reproductive biology and evolution in the pteridophyta. They formed the dominant part of the earths during palaeozoic and mesozoic periods on soral evolution. Complete 18s ribosomal rna sequence data from representatives of all extant pteridophyte lineages together with rna sequences from different seed plants were used to infer a molecular phylogeny of vascular plants that included all major land plant lineages. Stomatal patterns in pteridophytes an evolutionary approach. Stelar evolution in pteridophytes ppt types of steles and its evolution in pteridophytes ppt what is stele. Featherplants are among the worlds most ancient plants, found as fossils in rocks 400 million years old. Pteridophytes article about pteridophytes by the free. They possess certain combinations of major characters which are not found in bryophytes or in phanerogams. The pteridophytes ferns and fern allies pteridophytes are vascular plants and have leaves known as fronds, roots and sometimes true stems, and tree ferns have full trunks. Haeckel 1866 called these groups of plants as pteridophytes because of their pinnate or feather like fronds leaves. In 1880, the cryptogams of the plant kingdom were divided. Stelar evolution of pteridophytes, sporangial organization homospory and heterospory.
A few pteridophytes are aquatic while still others are. The structure and function of xylem in seed free vascular plants. Many aspects of difficult interpretation exist in the phylogenetic history of land plants. Filicales, introductions to both fossil and recent plant taxa, links. Medicinal potential of pteridophytesan antihyperglycemic and antinociceptive activity evaluation of methanolic extract of whole plants of christella dentata. Characteristics of pteridophytes, morphology of pteridophytes, reproduction of pteridophytes, homosporous and heterosporous pteridophytes, megaspore and microspores, gametophytes of pteridophytes, fertilization, zygote and embryo of. Their leaves are called fronds, which are highly divided except in a few isolated species.
Coal is made largely of fossilized featherplants of the. 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 forestdwelling plants. They generally live as an understory plant in shaded, moist areas, although their habitat varies considerably. In protostele, the vascular tissue is a solid mass and the central core of the xylem is completely surrounded by the strand of phloem. According to him, the primitive type of stele is protostele.
As they produce neither flowers nor seeds, they are referred to as cryptogams. The sporophyte was the dominant phase of the life cycle of these early pteridophytes. Ferns belong to a group of plants called featherplants or pteridophytes, along with club mosses and horsetails. All books are in clear copy here, and all files are secure so dont worry about it. Some other uses are ferns provide natural vegetation thats important to both wildlife and birds. 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. It is speculated that life began in the oceans, and through millions of years of evolution, life slowly adapted on to dry land. And among the first of the plants to truly live on land were the pteridophytes. Ferns, horsetails often treated as ferns, and lycophytes clubmosses, spikemosses, and quillworts are all pteridophytes. Most of the pteridophytes ferns and fernallies show their luxuriant and vigorous growth during the rainy season particularly in the hilly regions usually above 1400 m altitude. Were pteridophytes always less abundant than phanerogamic plants. Phytochemical studies in brazilian pteridophytes soeder 1985 reported a large inventory of papers that appeared between 1966 and 1984 on the chemical constituents of pteridophytes. This author lists a total of 671 references, but only one work had been carried out in brazil miraglia et al.
Stelar evolution of pteridophytes sporangial organization. Molecular evolution of pteridophytes and their relationship to seed plants. Pteridophyta is the most highly evolved group among the cryptogams. Feb 06, 2016 this feature is not available right now. Useful notes on the classification of pteridophytes.
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