Non-vascular plants is a general term for those plants Plants are living organisms belonging to the kingdom Plantae. They include familiar organisms such as trees, herbs, bushes, grasses, vines, ferns, mosses, and green algae. The scientific study of plants, known as botany, has identified about 350,000 extant species of plants, defined as seed plants, bryophytes, ferns and fern allies. As of 2004, without a vascular system Vascular tissue is a complex conducting tissue, formed of more than one cell type, found in vascular plants. The primary components of vascular tissue are the xylem and phloem. These two tissues transport fluid and nutrients internally. There are also two meristems associated with vascular tissue: the vascular cambium and the cork cambium. All the (xylem In vascular plants, xylem is one of the two types of transport tissue, phloem being the other. The word "xylem" is derived from classical Greek ξυλον , "wood", and indeed the best-known xylem tissue is wood, though it is found throughout the plant. Its basic function is to transport water and phloem In vascular plants, phloem is the living tissue that carries organic nutrients , particularly sucrose, a sugar, to all parts of the plant where needed. In trees, the phloem is the innermost layer of the bark, hence the name, derived from the Greek word φλόος (phloos) "bark". The phloem is concerned mainly with the transport of). Although non-vascular plants lack these particular tissues, a number of non-vascular plants possess tissues specialized for internal transport of water Water is a ubiquitous chemical substance that is composed of hydrogen and oxygen and is essential for all known forms of life.
Non-vascular plants have no roots In vascular plants, the root is the organ of a plant that typically lies below the surface of the soil. This is not always the case, however, since a root can also be aerial or aerating (growing up above the ground or especially above water). Furthermore, a stem normally occurring below ground is not exceptional either (see rhizome). So, it is, stems A stem is one of two main structural axes of a vascular plant. The stem is normally divided into nodes and internodes, the nodes hold buds which grow into one or more leaves, inflorescence , cones or other stems etc. The internodes distance one node from another. The term shoots is often confused with stems; shoots generally refer to new fresh, or leaves In botany, a leaf is an above-ground plant organ specialized for photosynthesis. For this purpose, a leaf is typically flat and thin. There is continued debate about whether the flatness of leaves evolved to expose the chloroplasts to more light or to increase the absorption of carbon dioxide. In either case, the adaption was made at the expense, since each of these structures is defined as containing vascular tissue Vascular tissue is a complex conducting tissue, formed of more than one cell type, found in vascular plants. The primary components of vascular tissue are the xylem and phloem. These two tissues transport fluid and nutrients internally. There are also two meristems associated with vascular tissue: the vascular cambium and the cork cambium. All the. The lobes (rounded parts) of the liverwort may look like leaves, but they are not true leaves because they have no xylem In vascular plants, xylem is one of the two types of transport tissue, phloem being the other. The word "xylem" is derived from classical Greek ξυλον , "wood", and indeed the best-known xylem tissue is wood, though it is found throughout the plant. Its basic function is to transport water or phloem In vascular plants, phloem is the living tissue that carries organic nutrients , particularly sucrose, a sugar, to all parts of the plant where needed. In trees, the phloem is the innermost layer of the bark, hence the name, derived from the Greek word φλόος (phloos) "bark". The phloem is concerned mainly with the transport of. Likewise, mosses and algae have no such tissues.
All plants have a life cycle with an alternation of generations The Alternation of generations describes the life cycle of plants, fungi and protists. A multicellular diploid phase alternates with a multicellular haploid phase. The term can be confusing for people familiar only with the life cycle of a typical animal. A more understandable name would be "alternation of phases of a single generation" between a diploid sporophyte All land plants, and some algae, have life cycles in which a haploid gametophyte generation alternates with a diploid sporophyte, the generation of a plant or alga that has a double set of chromosomes. A multicellular sporophyte generation or phase is present in the life cycle of all land plants and in some green algae. For common flowering plants and a haploid gametophyte The gametophyte produces male or female gametes , by a process of cell division called mitosis. The fusion of male and female gametes produces a diploid zygote, which develops by repeated mitotic cell divisions into a multicellular sporophyte. Because the sporophyte is the product of the fusion of two haploid gametes, its cells are diploid,, but nonvascular plants include the only plants that have a dominant gametophyte generation. In these plants, the sporophytes grow attached and are dependent on gametophytes for taking in water and other materials. Non-vascular plants grow from spores.
Non-vascular groups
The term non-vascular plant is no longer used in scientific nomenclature. Non-vascular plants include two distantly related groups:
- Bryophytes Bryophytes are all embryophytes that are non-vascular: they have tissues and enclosed reproductive systems, but they lack vascular tissue that circulates liquids. They neither have flowers nor produce seeds, reproducing via spores. The term bryophyte comes from Greek βρύον - bryon, "tree-moss, oyster-green" + φυτόν - fyton & - the Bryophyta Mosses are small, soft plants that are typically 1–10 cm tall, though some species are much larger. They commonly grow close together in clumps or mats in damp or shady locations. They do not have flowers or seeds, and their simple leaves cover the thin wiry stems. At certain times mosses produce spore capsules which may appear as beak-like (mosses), the Marchantiophyta The Marchantiophyta [mɑːˌkæntiˈɑːfɪtə] (help·info) are a division of bryophyte plants commonly referred to as hepatics or liverworts. Like other bryopeos, they have a gametophyte-dominant life cycle, in which cells of the plant carry only a single set of genetic information (liverworts), and the Anthocerotophyta Hornworts are a group of bryophytes, or non-vascular plants, comprising the division Anthocerotophyta. The common name refers to the elongated horn-like structure, which is the sporophyte. The flattened, green plant body of a hornwort is the gametophyte plant (hornworts). In these groups, the primary plants are the haploid Ploidy is the number of complete sets of chromosomes in a biological cell. In humans, the somatic cells that compose the body are diploid , but sex cells (sperm and egg) are haploid. In contrast, tetraploidy (four sets of chromosomes) is a type of polyploidy and is common in plants, and not uncommon in amphibians, reptiles, and various species of gametophytes The gametophyte produces male or female gametes , by a process of cell division called mitosis. The fusion of male and female gametes produces a diploid zygote, which develops by repeated mitotic cell divisions into a multicellular sporophyte. Because the sporophyte is the product of the fusion of two haploid gametes, its cells are diploid,, with the only diploid Ploidy is the number of complete sets of chromosomes in a biological cell. In humans, the somatic cells that compose the body are diploid , but sex cells (sperm and egg) are haploid. In contrast, tetraploidy (four sets of chromosomes) is a type of polyploidy and is common in plants, and not uncommon in amphibians, reptiles, and various species of portion being the attached sporophyte All land plants, and some algae, have life cycles in which a haploid gametophyte generation alternates with a diploid sporophyte, the generation of a plant or alga that has a double set of chromosomes. A multicellular sporophyte generation or phase is present in the life cycle of all land plants and in some green algae. For common flowering plants, consisting of a stalk and sporangium A sporangium is a plant, fungal, or algal structure producing and containing spores. Sporangia occur in angiosperms, gymnosperms, ferns, fern allies, bryophytes, algae, and fungi. Their spores are sometimes called sporangiospores. Because these plants lack water-conducting tissues, they can't become as big as most vascular plants Vascular plants are those plants that have lignified tissues for conducting water, minerals, and photosynthetic products through the plant. Vascular plants include the ferns, clubmosses, flowering plants, conifers and other gymnosperms. Scientific names for the group include Tracheophyta and Tracheobionta, but neither name is very widely used.[.
- Algae Algae are a large and diverse group of simple, typically autotrophic organisms, ranging from unicellular to multicellular forms. The largest and most complex marine forms are called seaweeds. They are photosynthetic, like plants, and "simple" because they lack the many distinct organs found in land plants. For that reason they are - especially the green algae The green algae are the large group of algae from which the embryophytes (higher plants) emerged. As such, they form a paraphyletic group, although the group including both green algae and embryophytes is monophyletic (and often just known as kingdom Plantae). The green algae include unicellular and colonial flagellates, usually but not always. Recent studies have demonstrated that the algae actually consist of several unrelated groups. It turns out that common features of living in water and photosynthesis Photosynthesis is a process that converts carbon dioxide into organic compounds, especially sugars, using the energy from sunlight. Photosynthesis occurs in plants, algae, and many species of Bacteria, but not in Archaea. Photosynthetic organisms are called photoautotrophs, since it allows them to create their own food. In plants, algae and were misleading as indicators of close relationship. Only the green algae are still considered relatives of the plants.
Both of these groups are occasionally termed the "lower plants"; the term "lower" refers to these plants' status as the earliest plants to evolve. However, the term "lower" plants is not precise, since it frequently is used to include some vascular Vascular tissue is a complex conducting tissue, formed of more than one cell type, found in vascular plants. The primary components of vascular tissue are the xylem and phloem. These two tissues transport fluid and nutrients internally. There are also two meristems associated with vascular tissue: the vascular cambium and the cork cambium. All the plants, the ferns A fern is any one of a group of about 20,000 species of plants classified in the phylum or division Pteridophyta, also known as Filicophyta. The group is also referred to as Polypodiophyta, (or Polypodiopsida when treated as a subdivision of tracheophyta ). This name is based on the concept of using type names for all levels of classification and fern allies Fern ally is a general term covering a somewhat diverse group of vascular plants that are not flowering plants and not true ferns. Like ferns, these plants disperse by shedding spores to initiate an alternation of generations.
In the past, the term non-vascular plant included not only all the algae Algae are a large and diverse group of simple, typically autotrophic organisms, ranging from unicellular to multicellular forms. The largest and most complex marine forms are called seaweeds. They are photosynthetic, like plants, and "simple" because they lack the many distinct organs found in land plants. For that reason they are, but also the fungi A fungus is a member of a large group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. The Fungi (pronounced /ˈfʌndʒaɪ/ or /ˈfʌŋɡaɪ/) are classified as a kingdom that is separate from plants, animals and bacteria. One major difference is that fungal cells have cell as well. Today, it is recognized that these groups are not closely related to plants, and have a very different biology Biology is the natural science concerned with the study of life and living organisms, including their structure, function, growth, origin, evolution, distribution, and taxonomy. The term biology in its modern sense appears to have been introduced independently by Karl Friedrich Burdach (1800), Gottfried Reinhold Treviranus (Biologie oder.
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[[zh:非維管植物]
Categories: Non-vascular plants | Plants
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Q. universities in canada that have Ph.D programs on lower plants such as algae, mosses, non-vascular plants ,etc
Asked by borhan_khollas - Sat Jan 21 12:52:55 2006 - - 2 Answers - 0 Comments
A. Hey, just bringing this old question up for a vote.
Answered by JaneofAllTrades - Wed Mar 22 23:45:59 2006
