Fronds in the largest species of ferns can reach some six metres in length. Dioicous pteridophytes produce only antheridia male organs or archegonia female organ on a single gametophyte body. Outside the stele lies the endodermis, which is the innermost cell layer of the cortex. Types of siphonostele solenostele nonoverlapping leaf traces. Nov 12, 2014 types of stele in pteridophytes and its evolution. Pteridophytes ferns and lycophytes are freesporing vascular plants that have a life cycle with alternating, freeliving gametophyte and sporophyte phases that are independent at maturity. The primary components of stele are xylem and phloem. Pteridophyta is the most highly evolved group among the cryptogams. Comparative study of morphology, anatomy, development, vegetative and. Some other uses are ferns provide natural vegetation thats important to both wildlife and birds. The body of the sporophyte is well differentiated into roots, stem and leaves. 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. Check out our resources for adapting to these times. Basic types of steles protostele central xylem, surrounding phloem.
According to the older botanists, the vascular bundle is the fundamental unit in the vascular system of pteridophytes and higher plants. An introduction to pteridophyta top results of your surfing an introduction to pteridophyta start download portable document format pdf and ebooks electronic books free online rating news 20162017 is books that can provide inspiration, insight, knowledge to the reader. The plant list includes a further 3,533 scientific plant names of infraspecific rank for the pteridophytes. Some pteridophytes are aquatic and some are epiphytes. Pteridophytes may represent the closest living relatives sister group to the seed plants. They are psilopsida, psilotopsida, lycopsida, sphenopsida, pteropsida and progymnospermopsida. Bryophytes general characters ppt mosses, liverworts and hornworts general characteristics of pteridophytes ppt. A pteridophyte is a vascular plant with xylem and phloem that disperses spores. This page was last modified on 20 december 2014, at 16.
Pteridophyta mcq multiple choice question and answer pteridophyta mcq with detailed explanation for interview, entrance and competitive exams. There are about eleven thousand different species of pteridophytes, making them the most diverse land plants after the. The innhabitants of dry land are selaginella rupestris, selaginella lepidophylla, equisetum arvens etc. Stelar theory also says that the cortex and the stele are the two fundamental. Types of stelar system and its evolution in pteridophytes the stele is defined as a central vascular cylinder, with or without pith. From wikieducator of a division pteridophyta of vascular plants such as a fern that have roots, stems, and leaves but lack flowers or seeds. On the basis of their anatomy jeffrey in 1902 divided the vascular plants into two types or stocks. As with all plants, in pteridophytes, meiosis is sporic, meaning that cells of the sporophyte undergo meiosis and generate spores that then develop into the gametophyte via mitosis. 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.
Jul 09, 2019 discuss the different types of stele found amoung pteridophytes. Pteridophyta general characteristics, classification and stelar system pteridophyta are the most primitive vascular plants. Classification of pteridophyta linkedin slideshare. 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. The term fern ally included under pteridophyta generally refers stellad vascular sporebearing plants that are not ferns, including lycopods, horsetails, whisk ferns and water ferns marsileaceaesalviniaceae and ceratopterisand even a much wider range of taxa. Types of siphonosteles cladosiphonic no leaf traces phyllosiphonic with leaf traces ectophloic phloem outside xylem. Types of stelar system and its evolution in pteridophytes. Stelar evolution in pteridophytes linkedin slideshare. Type of stelar system in pteridophytes all part inside endodermis are called stele. O based on the position and distribution of phloem, two types of siphonostles reported among pteridophytes are a ectophloic siphonostele and b amphiphloic siphonostele. On account of the close similarity shown between the acacian system and that of the ancient lyginopteris oldhamia, it is likely that the five sympodial structure is the ancestral form. Pteridophytes ferns and fern allies the plant list. Content is available under the creative commons attribution share.
Because pteridophytes produce neither flowers nor seeds, they are sometimes referred to as cryptogams, meaning that their means of reproduction is hidden. There are several basic categories of sexuality in pteridophytes. General features, classification, stellar system and its evolution. Bower1930proposed that the variation in stellar form was directly related to the size of the plant and its ability to provide, through the primary vascular system, the. Pteridophyta characteristics, life cycle, classification. In pteridophytes the stele is divided in to different type on the basis of arrangement of. Central xylem core with radiating ribs or a star shaped appearance surrounded by phloem. Doultion as a model for understanding the relationship between the shoot and root, and for discussing the evolution of vascular plant morphology. Primitive siphonostele protostele with central pith. Some of the species belonging to this division have small leaves called as the microphylls. Similar to the life cycle of seed plants, the pteridophytes also involves the alternation of generations in its life cycle. Paper iii diversity of pteridophytes, gymnosperms and elementary palaeobotany m. Ebook an introduction to pteridophyta as pdf download.
Pteridophytes biology encyclopedia plant, body, different. Ferns, horsetails often treated as ferns, and lycophytes clubmosses, spikemosses, and quillworts are all pteridophytes. Pteridophytes or pteridophyta, in the broad interpretation of the term, are vascular plants plants with xylem and phloem that reproduce and disperse via spores. Seed plants include the angiosperms, the conifers, and a smaller assortment of other plants. For most of this time it was restricted to water where it flourished and evolved. Pteridophytes are mostly terrestrial sometimes growing in the moist and shady regions. International research botany group 2017 international. In this lesson, well discover the characteristics, classification, and life cycle of the group pteridophyta, which includes plant species like ferns and horsetails. Secretory tissue in plants ppt structure, classification and examples pteridospermales ppt general characteristics, classification and affinities cassava mosaic disease ppt. Various animals use the fronds as food while birds and small creatures use the plants for cover. What are euphylls and how did they most likely evolve. Types of stele and its evolution in pteridophytes youtube. Economic importance of pteridophytes,several ferns such as angiopteris, asplenium, marattia, microsorium, nephrolepis, phymatodes, etc.
Monoicous pteridophytes produce both antheridia and archegonia on the same gametophyte body. Therefore the pericycle xylem and phloem together is called stele. Download objective type questions of pteridophyta pdf visit our pdf store. Tree fern growth strategy in the late devonian cladoxylopsid species pietzschia levis from the study of its stem and root system american journal of botany. 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. Jul 06, 2009 for the best answers, search on this site evolutionarily, they are the first terrestrial plants to possess vascular tissues xylem and phloem,in pteridophytes, the main plant body is a sporophyte which is differentiated into true root, stem and leaves. The plant list includes 46,428 scientific plant names of species rank for the pteridophytes. Schmidt recognized the two principal types of steles in. In pteridophytes the stele is divided in to different type on the basis of arrangement of xylem and phloem. Firstly, pteridophytes are the vascular plants plants having xylem and phloem that reproduces via spores.
Therefore pteridophytes are no longer considered to form a valid taxon, but the term is still used as an informal way to refer to ferns, horsetails, clubmosses and whisk ferns. Pteridophytes, also known as vascular cryptogams and ferns and fern allies, comprise about 12 000 species of vascular plants that do not produce. In this article we will discuss about the classification of pteridophytes. Stelar theory, components of stele, different types of steles in plants, protostele. Pteridophyta objective type questions pdf download. Jeffrey 1898, for the first time pointed out the stelar theory from the point of view of the phylogeny. Besides having various medicinal properties, the pteridophytes are also employed for a variety of commercial and environmental purposes. 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. The innhabitants of dry land are selaginella rupestris, selaginella lepidophylla, equisetum arvens etc pteridophytes shows large variation in the form, size and habit.
Some of the most important types stelar system in ferns are as follows. In 1880, the cryptogams of the plant kingdom were divided. The stele is a real entity and present universally in all axis of higher plants. The modern classification of pteridophytes have been suggested by many scientist according to the sporne1975 pteridophytes have been classified into six classes. However, the pteridophytes differ from mosses and seed plants in that both generations are independent and freeliving.
Most pteridophytes are terrestrial and grow in moist and shady places while some flourish well in open, dry places especially in xeric conditions. Endodermis is the boundary between cortex and stele. A concept based exclusive material pteridophytes, gymnosperms. They have leaves, roots, stem and sometimes trunks also. 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. Stelar evolution in pteridophytes ppt types of steles and its evolution in pteridophytes ppt what is stele. In a vascular plant, the stele is the central part of the root or stem containing the tissues derived from the procambium.
There are five types of protostele in pteridophytes they are 1. Eichler 1883 divided the plant kingdom into cryptogamia and phanerogamia. The maximum growth of such plants was during the carboniferous and permian periods, when the forests of the world were composed mainly of pteridophytes lycopods, giant equisetum and gymnosperms mainly 3. Equisetum amphiphloic outer and inner rings of phloem, xylem central. Pteridophyte definition of pteridophyte by merriamwebster. Tissues like pericycle, medullary rays and pith are also the components of stele. Art thesis papers your professional writers delivered on a ridiculous deadline and i got an amazing grade. The main difference between the acacian system in fig. The printed version, however, was effectively published on 6 june 20. The sporophyte is the conspicuous and familiar plant body. This classification is a modification is a modification of reimers 1954 system. Pteridophytes introduction, authors and addresses, systematic list, glossary, and key to tribes.
Schmidt recognized the two principal types of steles in pteridophytes. Van tieghem and douliot 1886 interpreted the plant body of a vascular plant in the different way. Thus, these characteristics make them horticulturally important plants. These include vascular tissue, in some cases ground tissue and a pericycle, which, if present, defines the outermost boundary of the stele. Some of the characters of pteridophytes are as follows. Classification of pteridophytes for a long time the division pteridophyta includedthe ferns, lycopods and horsetails. The concept of the stele was developed in the late 19th century by french botanists p. In pteridophytes, gametes are produced via mitosis from special cells of the gametophyte. The pteridophytes show heteromorphic alternation of generation. 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.
They proposed the stellar theory, according to which the root and stem have the same basic structure consisting of two fundamental units the cortex and the central cylinder. As they produce neither flowers nor seeds, they are referred to as cryptogams. The terms distinguish between types of gametophyte sexuality. The plant body can be divided into a true root, stem, and leaves. A good portion of the image references used here tap fine image resources for nonflowering vascular plants.