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Duckweed
Lemnoideae is a subfamily of flowering aquatic plants, known as duckweeds, water lentils, or water lenses. They float on or just beneath the surface of still or slow-moving bodies of fresh water and wetlands. Also known as bayroot, they arose from within the arum or aroid family (Araceae), so often are classified as the subfamily Lemnoideae within the family Araceae. Other classifications, particularly those created prior to the end of the twentieth century, place them as a separate family, Lemnaceae. These plants have a simple structure, lacking an obvious stem or leaves. The greater part of each plant is a small organized "thallus" or "frond" structure only a few cells thick, often with air pockets (aerenchyma) that allow it to float on or just under the water surface. Depending on the species, each plant may have no root or may have one or more simple rootlets. Reproduction is mostly by asexual budding (vegetative reproduction), which occurs from a meristem enclosed at the b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lemna
''Lemna'' is a genus of free-floating aquatic plants referred to by the common name "duckweed". They are morphologically divergent members of the arum family Araceae. These rapidly growing plants have found uses as a model system for studies in community ecology, basic plant biology, ecotoxicology, and production of biopharmaceuticals, and as a source of animal feeds for agriculture and aquaculture. Currently, 14 species of ''Lemna'' are recognised. Taxonomy These duckweeds were previously placed in a separate flowering plant family, the Lemnaceae, but they are now considered to be members of the Araceae. Description ''Lemna'' species grow as simple free-floating thalli on or just beneath the water surface. Most are small, not exceeding 5 mm in length, except '' Lemna trisulca'', which is elongated and has a branched structure. ''Lemna'' thalli have a single root, which distinguishes this genus from the related genera '' Wolffia'' (lacks roots), ''Spirodela'' and ''Landol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spirodela Polyrrhiza
''Spirodela polyrhiza'' ( ''S. polyrrhiza'') is a species of duckweed known by the common names common duckmeat, greater duckweed, great duckmeat, common duckweed, and duckmeat. It can be found nearly worldwide in many types of freshwater habitat. Description ''Spirodela polyrhiza'' is a Perennial plant, perennial aquatic plant usually growing in dense colonies, forming a mat on the water surface. Each plant is a smooth, round, flat disc 0.5 to 1.0 cm wide. Its upper surface is mostly green, sometimes red, while the lower surface is dark red. It produces several minute roots and a pouch containing male and female flowers. The top part dies in the fall and the plant often overwinters as a Turion (botany), turion. The turion sinks to the bottom of the water body and stays in a Dormancy, dormant phase, until water temperature reaches 15 °C. The turions then germinate on the bottom of the water body and start a new life cycle. As this species lives in ponds and slow-movin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wolffia
''Wolffia'' is a genus of aquatic plants with a cosmopolitan distribution. They include the smallest flowering plants on Earth. Commonly called watermeal or rootless duckweed, these aquatic plants resemble specks of cornmeal floating on the water. They often float together in pairs or form floating mats with related plants, such as ''Lemna'' and ''Spirodela'' species. Description ''Wolffia'' are free-floating aquatic plants with fronds that are nearly spherical to cylindrical in shape and lack airspaces or veins. They do not have roots. Their rarely seen flowers originate from a cavity on the upper surface of the frond, and each flower has one stamen and one pistil. Although ''Wolffia'' can reproduce by seed, they usually use vegetative reproduction. A mother frond has a terminal conical cavity from which it produces daughter fronds. Physiology The growth rate of ''Wolffia'' varies within and among species. The rates of photosynthesis and respiration also vary proportionat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aquatic Plant
Aquatic plants, also referred to as hydrophytes, are vascular plants and Non-vascular plant, non-vascular plants that have adapted to live in aquatic ecosystem, aquatic environments (marine ecosystem, saltwater or freshwater ecosystem, freshwater). In lakes, rivers and wetlands, aquatic vegetations provide cover for aquatic animals such as fish, amphibians and aquatic insects, create substrate (marine biology), substrate for benthic invertebrates, produce oxygen via photosynthesis, and serve as food for some herbivorous wildlife. Familiar examples of aquatic plants include Nymphaeaceae, waterlily, Nelumbo, lotus, duckweeds, mosquito fern, floating heart, water milfoils, Hippuris, mare's tail, water lettuce, water hyacinth, and algae. Aquatic plants require special adaptation (biology), adaptations for prolonged inundation in water, and for buoyancy, floating at the water surface. The most common adaptation is the presence of lightweight internal packing cells, aerenchyma, but floa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wolffia Globosa
''Wolffia globosa'' is a species of flowering plant known by the common names Asian watermeal and duckweed. It is native to Asia and is found in parts of the Americas and Africa, where it is an introduced species. It grows in mats on the surface of calm, freshwater bodies, such as ponds, lakes, and marshes. It is a very tiny, oval-shaped plant with no leaves, stems, or roots. The body of the plant, a transparent green frond, is less than a millimeter wide. In one human experiment, processed ''W. globosa'' was reported to provide dietary protein and vitamin B12. ''Wolffia globosa'' has been described as the world's smallest flowering plant, at in diameter. Known in Thai as ''Pham'' (ผํา), it is a popular item in Thai cuisine, especially in Isan Northeast Thailand or Isan (Isan language, Isan/, ; ; also written as Isaan, Isarn, Issarn, Issan, Esan, or Esarn; from Pāli ''isāna'' or Sanskrit ईशान्य ''īśānya'' "northeast") consists of 20 provinces in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spirodela
''Spirodela'' is a genus of aquatic plants, one of several genera containing plants commonly called duckweed. ''Spirodela'' species are members of the Araceae under the APG II system. They were formerly members of the Lemnaceae. Description ''Spirodela'' species are free-floating plants that have their stem transformed into leaf-like structures called fronds; each plant is represented by a frond with roots, therefore they do not have leaves. Two to five plants may remain connected to each other. Plants are green, but may turn red due to the presence of anthocyanin. Multiple root In vascular plants, the roots are the plant organ, organs of a plant that are modified to provide anchorage for the plant and take in water and nutrients into the plant body, which allows plants to grow taller and faster. They are most often bel ...s (5 to 20, depending on the species) emerge from each frond. ''Spirodela'' is larger () than '' Lemna'' ( – , with one root per frond). Certain sp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Araceae
The Araceae are a family of monocotyledonous flowering plants in which flowers are borne on a type of inflorescence called a spadix. The spadix is usually accompanied by, and sometimes partially enclosed in, a spathe (or leaf-like bract). Also known as the arum family, members are often colloquially known as aroids. This family of 114 genera and about 3,750 known species is most diverse in the New World tropics, although also distributed in the Old World tropics and northern temperate regions. Description Within the Araceae, species are often rhizomatous or tuberous; many are epiphytic, creeping lianas or vining plants, and the leaves and tissues of the entire plant nearly always contains irritating calcium oxalate crystals or raphides, in varying degrees. The foliage can vary considerably from species to species. The majority of species produce an inflorescence consisting of a spadix (which some compare to a corn cob, in appearance), which is nearly always surrounded ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wetlands
A wetland is a distinct semi-aquatic ecosystem whose groundcovers are flooded or saturated in water, either permanently, for years or decades, or only seasonally. Flooding results in oxygen-poor ( anoxic) processes taking place, especially in the soils. Wetlands form a transitional zone between waterbodies and dry lands, and are different from other terrestrial or aquatic ecosystems due to their vegetation's roots having adapted to oxygen-poor waterlogged soils. They are considered among the most biologically diverse of all ecosystems, serving as habitats to a wide range of aquatic and semi-aquatic plants and animals, with often improved water quality due to plant removal of excess nutrients such as nitrates and phosphorus. Wetlands exist on every continent, except Antarctica. The water in wetlands is either freshwater, brackish or saltwater. The main types of wetland are defined based on the dominant plants and the source of the water. For example, ''marshes'' are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wolffiella
''Wolffiella'' is a genus of aquatic plants commonly called duckweeds in the family Araceae The Araceae are a family of monocotyledonous flowering plants in which flowers are borne on a type of inflorescence called a spadix. The spadix is usually accompanied by, and sometimes partially enclosed in, a spathe (or leaf-like bract). Also .... Common names for plants in this genus include bogmat and mud-midget. They are rootless and have a keel that allows them to maintain their orientation in the water. They are small, measuring to in width. Selected species *'' Wolffiella caudata'' *'' Wolffiella denticulata'' *'' Wolffiella gladiata'' *'' Wolffiella hyalina'' *'' Wolffiella lingulata'' *'' Wolffiella neotropica'' *'' Wolffiella oblonga'' *'' Wolffiella repanda'' *'' Wolffiella rotunda'' *'' Wolffiella welwitschii'' References Further reading *Bown, Deni (2000). ''Aroids: Plants of the Arum Family''. Timber Press. . Lemnoideae Araceae genera {{Araceae-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein (nutrient)
Proteins are essential nutrients for the human body. They are one of the constituents of Tissue (biology), body tissue and also serve as a Fuel, fuel source. As fuel, proteins have the same energy density as carbohydrates: 17 Joule, kJ (4 Calories, kcal) per gram. The defining characteristic of protein from a nutritional standpoint is its amino acid composition. Proteins are polymer chains made of amino acids linked by peptide bonds. During human digestion, proteins are broken down in the stomach into smaller polypeptide chains via hydrochloric acid and protease actions. This is crucial for the absorption (small intestine), absorption of the essential amino acids that cannot be biosynthesized by the body. There are nine essential amino acids that humans must obtain from their diet to prevent protein–energy malnutrition, protein-energy malnutrition and resulting death. They are phenylalanine, valine, threonine, tryptophan, methionine, leucine, isoleucine, lysine, and histidin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pistil
Gynoecium (; ; : gynoecia) is most commonly used as a collective term for the parts of a flower that produce ovules and ultimately develop into the fruit and seeds. The gynoecium is the innermost whorl (botany), whorl of a flower; it consists of (one or more) ''#Pistil, pistils'' and is typically surrounded by the pollen-producing plant reproductive morphology, reproductive organs, the stamens, collectively called the androecium. The gynoecium is often referred to as the "female" portion of the flower, although rather than directly producing female gametes (i.e. egg cells), the gynoecium produces megaspores, each of which develops into a female gametophyte which then produces egg cells. The term gynoecium is also used by botanists to refer to a cluster of archegonia and any associated modified leaves or stems present on a gametophyte shoot in mosses, Marchantiophyta, liverworts, and hornworts. The corresponding terms for the male parts of those plants are clusters of antheridiu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Waterfowl
Anseriformes is an order of birds also known as waterfowl that comprises about 180 living species of birds in three families: Anhimidae (three species of screamers), Anseranatidae (the magpie goose), and Anatidae, the largest family, which includes over 170 species of waterfowl, among them the ducks, geese, and swans. Most modern species in the order are highly adapted for an aquatic existence at the water surface. With the exception of screamers, males have penises, a trait that has been lost in the Neoaves, the clade consisting of all other modern birds except the galliformes and paleognaths. Due to their aquatic nature, most species are web-footed. Evolution Anseriformes are one of only two types of modern bird to be confirmed present during the Mesozoic alongside the other dinosaurs, and in fact were among the very few birds to survive their extinction, along with their cousins, the Galliformes. These two groups only occupied two ecological niches during the Mesozoic, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
