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Thallose
Thallus (plural: thalli), from Latinized Greek (), meaning "a green shoot" or "twig", is the vegetative tissue of some organisms in diverse groups such as algae, fungi, some liverworts, lichens, and the Myxogastria. Many of these organisms were previously known as the thallophytes, a polyphyletic group of distantly related organisms. An organism or structure resembling a thallus is called thalloid, thallodal, thalliform, thalline, or thallose. A thallus usually names the entire body of a multicellular non-moving organism in which there is no organization of the tissues into organs. Even though thalli do not have organized and distinct parts (leaves, roots, and stems) as do the vascular plants, they may have analogous structures that resemble their vascular "equivalents". The analogous structures have similar function or macroscopic structure, but different microscopic structure; for example, no thallus has vascular tissue. In exceptional cases such as the Lemnoideae, where t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marchantiophyta
The Marchantiophyta () are a division of non-vascular land plants commonly referred to as hepatics or liverworts. Like mosses and hornworts, they have a gametophyte-dominant life cycle, in which cells of the plant carry only a single set of genetic information. It is estimated that there are about 9000 species of liverworts. Some of the more familiar species grow as a flattened leafless thallus, but most species are leafy with a form very much like a flattened moss. Leafy species can be distinguished from the apparently similar mosses on the basis of a number of features, including their single-celled rhizoids. Leafy liverworts also differ from most (but not all) mosses in that their leaves never have a costa (present in many mosses) and may bear marginal cilia (very rare in mosses). Other differences are not universal for all mosses and liverworts, but the occurrence of leaves arranged in three ranks, the presence of deep lobes or segmented leaves, or a lack of clearly diff ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pellia Epiphylla 200108
''Pellia'' is a small but widespread genus of liverworts in the cool and temperate regions of the northern hemisphere. It is classified in Order (biology), order Pelliales and is a member of the Family (biology), family Pelliaceae within that order. Süsswassertang, a plant grown submerged in aquarium, aquaria was once considered to be ''Pellia endiviifolia'', but is now known to be the indeterminate gametophyte of a ''Lomariopsis'' species, a type of fern. Species Taxonomy based on work by Söderström et al. 2016 * ''Pellia cordaeana'' Trevisan 1877 * ''Pellia crispa'' Kummer 1875 * ''Pellia gottscheana'' Kreh 1909 * ''Pellia longifolia'' Kummer 1875 * ''Pellia undulata'' Kummer 1875 * (''Apopellia'') Grolle 1983a ** ''Pellia alpicola, P. (A.) alpicola'' (Schuster 1991) Damsholt 2007 ** ''Pellia endiviifolia, P. (A.) endiviifolia'' (Dickson 1801) Dumortier 1835 ** ''Pellia megaspora, P. (A.) megaspora'' Schuster 1981 * (''Pellia'') Raddi 1818 ** ''Pellia appalachiana, P. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plant Stem
A stem is one of two main structural axes of a vascular plant, the other being the root. It supports leaves, flowers and fruits, transports water and dissolved substances between the roots and the shoots in the xylem and phloem, stores nutrients, and produces new living tissue. The stem can also be called halm or haulm. The stem is normally divided into nodes and internodes: * The nodes hold one or more leaves, as well as buds which can grow into branches (with leaves, conifer cones, or flowers). Adventitious roots may also be produced from the nodes. * The internodes distance one node from another. The term "shoots" is often confused with "stems"; "shoots" generally refers to new fresh plant growth including both stems and other structures like leaves or flowers. In most plants stems are located above the soil surface but some plants have underground stems. Stems have four main functions which are: * Support for and the elevation of leaves, flowers, and fruits. The stems ke ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Horsetail
''Equisetum'' (; horsetail, snake grass, puzzlegrass) is the only living genus in Equisetaceae, a family of ferns, which reproduce by spores rather than seeds. ''Equisetum'' is a "living fossil", the only living genus of the entire subclass Equisetidae, which for over 100 million years was much more diverse and dominated the understorey of late Paleozoic forests. Some equisetids were large trees reaching to tall. The genus ''Calamites'' of the family Calamitaceae, for example, is abundant in coal deposits from the Carboniferous period. The pattern of spacing of nodes in horsetails, wherein those toward the apex of the shoot are increasingly close together, is said to have inspired John Napier to invent logarithms. Modern horsetails first appeared during the Jurassic period. A superficially similar but entirely unrelated flowering plant genus, mare's tail (''Hippuris''), is occasionally referred to as "horsetail", and adding to confusion, the name "mare's tail" is sometimes ap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clubmoss
Lycopodiopsida is a class of vascular plants known as lycopods, lycophytes or other terms including the component lyco-. Members of the class are also called clubmosses, firmosses, spikemosses and quillworts. They have dichotomously branching stems bearing simple leaves called microphylls and reproduce by means of spores borne in sporangia on the sides of the stems at the bases of the leaves. Although living species are small, during the Carboniferous, extinct tree-like forms formed huge forests that dominated the landscape and contributed to coal deposits. The nomenclature and classification of plants with microphylls varies substantially among authors. A consensus classification for extant (living) species was produced in 2016 by the Pteridophyte Phylogeny Group (PPG I), which places them all in the class Lycopodiopsida, which includes the classes Isoetopsida and Selaginellopsida used in other systems. (See Table 2.) Alternative classification systems have used ranks fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gametophyte
A gametophyte () is one of the two alternation of generations, alternating multicellular organism, multicellular phases in the life cycles of plants and algae. It is a haploid multicellular organism that develops from a haploid spore that has one set of chromosomes. The gametophyte is the Sexual reproduction of plants, sexual phase in the life cycle of plants and algae. It develops sex organs that produce gametes, haploid sex cells that participate in fertilization to form a diploid zygote which has a double set of chromosomes. Cell division of the zygote results in a new diploid multicellular organism, the second stage in the life cycle known as the sporophyte. The sporophyte can produce haploid spores by meiosis that on germination produce a new generation of gametophytes. Algae In some multicellular green algae (''Ulva lactuca'' is one example), red algae and brown algae, sporophytes and gametophytes may be externally indistinguishable (isomorphic). In ''Ulva (genus), Ulv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frond
A frond is a large, divided leaf. In both common usage and botanical nomenclature, the leaves of ferns are referred to as fronds and some botanists restrict the term to this group. Other botanists allow the term frond to also apply to the large leaves of cycads, as well as palms (Arecaceae) and various other flowering plants, such as mimosa or sumac. "Frond" is commonly used to identify a large, compound leaf, but if the term is used botanically to refer to the leaves of ferns and algae it may be applied to smaller and undivided leaves. Fronds have particular terms describing their components. Like all leaves, fronds usually have a stalk connecting them to the main stem. In botany, this leaf stalk is generally called a petiole, but in regard to fronds specifically it is called a stipe, and it supports a flattened blade (which may be called a lamina), and the continuation of the stipe into this portion is called the rachis. The blades may be simple (undivided), pinnatifid ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seaweed
Seaweed, or macroalgae, refers to thousands of species of macroscopic, multicellular, marine algae. The term includes some types of '' Rhodophyta'' (red), ''Phaeophyta'' (brown) and ''Chlorophyta'' (green) macroalgae. Seaweed species such as kelps provide essential nursery habitat for fisheries and other marine species and thus protect food sources; other species, such as planktonic algae, play a vital role in capturing carbon, producing at least 50% of Earth's oxygen. Natural seaweed ecosystems are sometimes under threat from human activity. For example, mechanical dredging of kelp destroys the resource and dependent fisheries. Other forces also threaten some seaweed ecosystems; a wasting disease in predators of purple urchins has led to a urchin population surge which destroyed large kelp forest regions off the coast of California. Humans have a long history of cultivating seaweeds for their uses. In recent years, seaweed farming has become a global agricultural practic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vegetative Reproduction
Vegetative reproduction (also known as vegetative propagation, vegetative multiplication or cloning) is any form of asexual reproduction occurring in plants in which a new plant grows from a fragment or cutting of the parent plant or specialized reproductive structures, which are sometimes called vegetative propagules. Many plants naturally reproduce this way, but it can also be induced artificially. Horticulturists have developed asexual propagation techniques that use vegetative propagules to replicate plants. Success rates and difficulty of propagation vary greatly. Monocotyledons typically lack a vascular cambium, making them more challenging to propagate. Background Plant propagation is the process of plant reproduction of a species or cultivar, and it can be sexual or asexual. It can happen through the use of vegetative parts of the plants, such as leaves, stems, and roots to produce new plants or through growth from specialized vegetative plant parts. While m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mycelium
Mycelium (plural mycelia) is a root-like structure of a fungus consisting of a mass of branching, thread-like hyphae. Fungal colonies composed of mycelium are found in and on soil and many other substrate (biology), substrates. A typical single spore germinates into a Monokaryon, monokaryotic mycelium, which cannot reproduce sexually; when two compatible monokaryotic mycelia join and form a dikaryotic mycelium, that mycelium may form sporocarp (fungi), fruiting bodies such as mushrooms. A mycelium may be minute, forming a colony that is too small to see, or may grow to span thousands of acres as in ''Armillaria''. Through the mycelium, a fungus absorbs nutrients from its environment. It does this in a two-stage process. First, the hyphae secrete enzymes onto or into the food source, which break down biopolymers, biological polymers into smaller units such as monomers. These monomers are then absorbed into the mycelium by facilitated diffusion and active transport. Mycelia are v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fungus
A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from the other eukaryotic kingdoms, which by one traditional classification include Plantae, Animalia, Protozoa, and Chromista. A characteristic that places fungi in a different kingdom from plants, bacteria, and some protists is chitin in their cell walls. Fungi, like animals, are heterotrophs; they acquire their food by absorbing dissolved molecules, typically by secreting digestive enzymes into their environment. Fungi do not photosynthesize. Growth is their means of mobility, except for spores (a few of which are flagellated), which may travel through the air or water. Fungi are the principal decomposers in ecological systems. These and other differences place fungi in a single group of related organisms, named the ''Eumycota'' (''true f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kelp
Kelps are large brown algae seaweeds that make up the order Laminariales. There are about 30 different genera. Despite its appearance, kelp is not a plant - it is a heterokont, a completely unrelated group of organisms. Kelp grows in "underwater forests" (kelp forests) in shallow oceans, and is thought to have appeared in the Miocene, 5 to 23 million years ago. The organisms require nutrient-rich water with temperatures between . They are known for their high growth rate—the genera ''Macrocystis'' and '' Nereocystis'' can grow as fast as half a metre a day, ultimately reaching .Thomas, D. 2002. ''Seaweeds.'' The Natural History Museum, London, p. 15. Through the 19th century, the word "kelp" was closely associated with seaweeds that could be burned to obtain soda ash (primarily sodium carbonate). The seaweeds used included species from both the orders Laminariales and Fucales. The word "kelp" was also used directly to refer to these processed ashes. Description In most kelp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
