Problems of cytology and evolution in the pteridophyta. This system is beneficial to the pteridophytes by easily enabling them to transport the necessary nutrients. A good portion of the image references used here tap fine image resources for nonflowering vascular plants. Pteridophytes fern and fern allies comprise more than 10,000 species throughout the world and are roughly distributed among 305 genera.
And among the first of the plants to truly live on land were the pteridophytes. Bryophyte vs pteridophyte difference and comparison diffen. Plants are eukaryotic, multicellular, autotrophic organisms that are capable of photosynthesizing. However, additional phylogenetic dilemmas are the evolution of bryophytes from algae and the transition from these first land plants to the pteridophytes. Another way you can look at sorus evolution is to consider the sporangia. Featherplants are among the worlds most ancient plants, found as fossils in rocks 400 million years old. Flowering plants are of two types gymnosperms and angiosperms which have common features like roots, stems, leaves, proper vascular tissues for transportation. Such a sorus is an aggregation of old and young sporangia that occur mixed and show no regular arrangement in a sorus.
With the commencement of monsoon about mid june, the ferns and fernallies start growing vigourously and luxuriantly. Examples of pteridophytes include ferns, horsetails, clubmosses, spikemosses and quillworts. We might on the one hand take first the most primitive families, as judged by soral and sporangial. The primary components of stele are xylem and phloem. Pteridophytes introduction, authors and addresses, systematic list, glossary, and key to tribes. Difference between bryophytes and pteridophytes with.
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. Therefore pteridophytes are also called vascular cryptogams. They formed the dominant part of the earths during palaeozoic and mesozoic periods on soral evolution. Medicinal potential of pteridophytes an antihyperglycemic and antinociceptive activity evaluation of methanolic extract of whole plants of christella dentata.
Megaphylls, microphylls and the evolution of leaf development. Like reptiles first true land animals that evolved after. Medicinal potential of pteridophytesan antihyperglycemic and antinociceptive activity evaluation of methanolic extract of whole plants of christella dentata. Pteridophyta characteristics, life cycle, classification. 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. Which of the following statements best describes the role of structure c in the nervous system. The more primitive ferns are called eusporangiate ferns and their sori are made up of a clump of simple sporangia that release their spores by opening up a pore or slit see first pic. 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. The following separation of the main growth forms of pteridophyta is proposed. 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.
Besides having various medicinal properties, the pteridophytes are also employed for a variety of commercial and environmental purposes. 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. What is one evolutionary advantage pteridophytes have over. Pteridophytes, also known as vascular cryptogams and ferns and fern allies, comprise about 12 000 species of vascular plants that do not produce. 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. May 26, 2017 ferns are pteridophytes which a have leaf finely divided into small parts, proper roots and underground stems. 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. We now turn to a consideration of the vascular system of the modern ferns, and in tracing its various modifications two alternatives are open to us.
Structure c is the basic cellular unit of the nervous system b. Two hundred twentyfour pteridophyte taxa, including hy brids and naturalizations, are known in hawaii. Various animals use the fronds as food while birds and small creatures use the plants for cover. The different species of selaginella are grown as the garden plants. The empirical basis of botanical systematics has been broadened far beyond the realm of macromorphological traits on which systematists have based their decisions for more than 200 years. Phytochemical studies in pteridophytes growing in brazil. Stelar evolution of pteridophytes sporangial organization. In many species, they are protected by an umbrellalike cover called the indusium. In general, pteridophytes have a long fossil record and. Stelar theory also says that the cortex and the stele are the two fundamental.
Pteridophytes ferns and fern allies the plant list. Stelar evolution of pteridophytes, sporangial organization homospory and heterospory. Pteridophytes or ferns first appeared in the fossil record more than 350 million years ago. O proposed by van tieghem and douliot in 1886 o major highlights in stellar theory are. Incongruence between primary sequence data and the distribution of a mitochondrial atp1group ii intron among ferns and horsetails. During the past two decades, the discoveryof fossil spores from as far back as the midordovician. Heterospory the earliest land plants, as well as many living pteridophytes, were homosporous, meaning that their sporophytes produced haploid spores of a. 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. The ferns are a large group included under pteridophytes. The body of the sporophyte is well differentiated into roots, stem and leaves.
Pteridophytes have a vascular system, unlike bryophytes. Pteridophytes or pteridophyta are vascular plants plants with xylem and phloem that reproduce and disperse via spores. Ferns are pteridophytes which a have leaf finely divided into small parts, proper roots and underground stems. The roots of the pteridophytes grow randomly or by chance and follow no specific pattern or system like the tap root of gymnosperms. Characteristic of pteridophytes, shape size and habitat. The young and old sporangia are indiscriminately mixed. This pdf version does not have an isbn or issn and is not therefore effectively published melbourne code, art. Molecular evolution of pteridophytes and their relationship. The stele is a real entity and present universally in all axis of higher plants. Pteridophyta is designed to fulfill the needs of undergraduate and postgraduate students of botany. Among green plant lineages, none are as speciesrich as vascular plants tracheophytes. A pteridophyte is a vascular plant with xylem and phloem that disperses spores. The printed version, however, was effectively published on 6 june 20.
Although this particular topic is beyond the aims of the present paper, let us remember that these tissues conditioned all tracheophyte sporophyte evolution. Life forms of pteridophyta, their origin and evolution. Pteridophytes general characters and life cycle of ferns email. A concept based exclusive material pteridophytes, gymnosperms. Ferns belong to a group of plants called featherplants or pteridophytes, along with club mosses and horsetails. Oct 10, 2017 key difference bryophytes vs pteridophytes vs gymnosperms. Were pteridophytes always less abundant than phanerogamic plants. At that time, what is now temperate europe and north america had climate conditions that favored yearround growth.
The pteridophytes occupy the intermediate position in between the bryophytes on one hand and the phanerogams on the other. The next step in the evolution of the sorus is the mixed sorus mixtae. Pteridophytes as commonly defined have a longer evolutionary history with a fossil record of more than 400 million years. The plant list includes 46,428 scientific plant names of species rank for the pteridophytes. Tissues like pericycle, medullary rays and pith are also the components of stele. Useful notes on the classification of pteridophytes. Why are pteridophytes better adapted to dry land than bryophytes. Some pteridophytes are aquatic marselia, azolla and. Haeckel 1866 called these groups of plants as pteridophytes because of their pinnate or feather like fronds leaves. The molecular data indicate that lycopsids are monophyletic and are the earliest diverging group within the vascular land plants. Missouri botanical garden and washington university. Tissue cells are joined into tubes that transport water and nutrients through the plant body.
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. A few pteridophytes are aquatic while still others are epiphytes. Each of these can be divided into life forms according to a series of morphological and other characters. Have female archegonia that produces eggs and male antheridia that produces sperm. Key difference bryophytes vs pteridophytes vs gymnosperms. Coal is made largely of fossilized featherplants of the. Difference between pteridophytes and gymnosperms major. View the article pdf and any associated supplements and figures for a period of 48 hours. The molecular data indicate that lycopsids are monophyletic and are the earliest diverging group within the vascular land. In the present article an attempt has been made to compile the information on various medicinal uses of sixteen commonly available pteridophytes of rajasthan. They are psilopsida, psilotopsida, lycopsida, sphenopsida, pteropsida and progymnospermopsida.
Stelar evolution in pteridophytes ppt types of steles and its evolution in pteridophytes ppt what is stele. The plant body is differentiated into roots, stem and leaves. Gymnosperms have a tap root while the pteridophytes do not. Similarities between bryophytes, pteridophytes, and gymnosperms.
Pteridophytes ferns chapter pdf available february 2003. This author lists a total of 671 references, but only one work had been carried out in brazil miraglia et al. The origin and early evolution of plants on land pdf. The current trends in the subject are explained in a simple, lucid and understandablewriting style. Pteridophytes pteridophytes is a general term for the vascular, free.
Evolution of hawaiian ferns and fern allies in relation to. The most characteristic feature of the pteridophytes is the presence. The modern classification of pteridophytes have been suggested by many scientist according to the sporne1975 pteridophytes have been classified into six classes. International research botany group 2017 international. The kingdom plantae is one of the most widespread kingdoms with over 300,000 different species. They possess certain combinations of major characters which are not found in bryophytes or in phanerogams. This pdf version does not have an isbn or issn and is not therefore effectively. The pteridophytes are an economically important group of plants. Some pteridophytes of medicinal importance from rajasthan. Pteridophytes constitute a significant and important group in the plant kingdom. Life cycles of lycopodium, selaginella, equisetum, adiantum and marsilea. Some pteridophytes are aquatic marselia, azolla and some are epiphytes ophioglossum pendulum.
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 plant list includes a further 3,533 scientific plant names of infraspecific rank for the pteridophytes. The tap root grows down vertically into soil and other roots sprout from it in horizontal or nearly horizontal directions. A few pteridophytes are aquatic while still others are.
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