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Indumentum
In biology, an indumentum (Latin, literally: "garment") is a covering of trichomes (fine "hairs") on a plant Davis, Peter Hadland and Heywood, Vernon Hilton (1963) ''Principles of angiosperm taxonomy'' Van Nostrandpage, Princeton, New Jersey, page 154, or of bristles (rarely scales) of an insect. In plants, indumentum types include: *pubescent *hirsute *pilose *lanate *villous *tomentose *stellate *scabrous *scurfy The indumentum on plants can have a wide variety of functions, including as anchorage in climbing plants (e.g., ''Galium aparine''), in transpiration control, in water absorption (''Tillandsia''), the reflection of solar radiation, increasing water-repellency (e.g., in the aquatic fern ''Salvinia''), in protection against insect predation, and in the trapping of insects (''Drosera'', ''Nepenthes'', ''Stylosanthes''). The use of an indumentum on insects can also be pollen-related, as on bees, sensory like whiskers, or for varied other uses including adhesion an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salvinia
''Salvinia'', a genus in the family Salviniaceae, is a floating fern named in honor of Anton Maria Salvini, a 17th-century Italian scientist. Watermoss is a common name for ''Salvinia''. The genus was published in 1754 by Jean-François Séguier, in his description of the plants found round Verona, ''Plantae Veronenses'' Twelve species are recognized, at least three of which (''S. molesta'', ''S. herzogii'', and ''S. minima'') are believed to be hybrids, in part because their sporangia are found to be empty. ''Salvinia'' is related to the other water ferns, including the mosquito fern ''Azolla''. Recent sources include both ''Azolla'' and ''Salvinia'' in Salviniaceae, although each genus was formerly given its own family. ''Salvinia'', like the other ferns in order Salviniales, are heterosporous, producing spores of differing sizes. However, leaf development in ''Salvinia'' is unique. The upper side of the floating leaf, which appears to face the stem axis, is morphologically ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ledum Groenlandicum 1-eheep (5097488087)
''Ledum'' was a genus in the family Ericaceae, including 8 species of evergreen shrubs native to cool temperate and subarctic regions of the Northern Hemisphere and commonly known as Labrador tea. It is now recognised as a subsection of section Rhododendron, subgenus ''Rhododendron'', of the genus ''Rhododendron''. Description ''Ledum'' species often grow together with poisonous plants such as bog-laurel and bog-rosemary, but certain species (e.g. '' L. groenlandicum'' and '' L. palustre'') are easily distinguished by the distinctive rust coloured fuzz on the bottom of leaves. Taxonomy Reclassification into Rhododendron Recent genetic evidence has shown that the species previously treated in this genus are correctly placed in the genus ''Rhododendron'', where they are now treated as ''Rhododendron'' subsect. ''Ledum''. Because some of the species names used in ''Ledum'' could not be used in ''Rhododendron'' (the names already having been used for other species already in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Poison
Poison is a chemical substance that has a detrimental effect to life. The term is used in a wide range of scientific fields and industries, where it is often specifically defined. It may also be applied colloquially or figuratively, with a broad sense. Whether something is considered a poison may change depending on the amount, the circumstances, and what living things are present. Poisoning could be accidental or deliberate, and if the cause can be identified there may be ways to neutralise the effects or minimise the symptoms. In biology, a poison is a chemical substance causing death, injury or harm to organisms or their parts. In medicine, poisons are a kind of toxin that are delivered passively, not actively. In industry the term may be negative, something to be removed to make a thing safe, or positive, an agent to limit unwanted pests. In ecological terms, poisons introduced into the environment can later cause unwanted effects elsewhere, or in other parts of the fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adhesion
Adhesion is the tendency of dissimilar particles or surfaces to cling to one another ( cohesion refers to the tendency of similar or identical particles/surfaces to cling to one another). The forces that cause adhesion and cohesion can be divided into several types. The intermolecular forces responsible for the function of various kinds of stickers and sticky tape fall into the categories of chemical adhesion, dispersive adhesion, and diffusive adhesion. In addition to the cumulative magnitudes of these intermolecular forces, there are also certain emergent mechanical effects. Surface energy Surface energy is conventionally defined as the work that is required to build an area of a particular surface. Another way to view the surface energy is to relate it to the work required to cleave a bulk sample, creating two surfaces. If the new surfaces are identical, the surface energy γ of each surface is equal to half the work of cleavage, W: γ = (1/2)W11. If the surf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Whisker
Vibrissae (; singular: vibrissa; ), more generally called Whiskers, are a type of stiff, functional hair used by mammals to sense their environment. These hairs are finely specialised for this purpose, whereas other types of hair are coarser as tactile sensors. Although whiskers are specifically those found around the face, vibrissae are known to grow in clusters at various places around the body. Most mammals have them, including all non-human primates and especially nocturnal mammals. Whiskers are sensitive tactile hairs that aid navigation, locomotion, exploration, hunting, social touch and perform other functions. This article is primarily about the specialised sensing hairs of mammals, but some birds, fish, insects, crustaceans and other arthropods are known to have similar structures also used to sense the environment. Etymology Vibrissae (from Latin 'to vibrate') from the characteristic motion seen in a small rodent that is otherwise sitting still. In medicine ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sensory Organ
A sense is a biological system used by an organism for sensation, the process of gathering information about the world through the detection of stimuli. (For example, in the human body, the brain which is part of the central nervous system receives signals from the senses which continuously receive information from the environment, interprets these signals, and causes the body to respond, either chemically or physically.) Although traditionally five human senses were identified as such (namely sight, smell, touch, taste, and hearing), it is now recognized that there are many more. Senses used by non-human organisms are even greater in variety and number. During sensation, sense organs collect various stimuli (such as a sound or smell) for transduction, meaning transformation into a form that can be understood by the brain. Sensation and perception are fundamental to nearly every aspect of an organism's cognition, behavior and thought. In organisms, a sensory organ con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pollen
Pollen is a powdery substance produced by seed plants. It consists of pollen grains (highly reduced microgametophytes), which produce male gametes (sperm cells). Pollen grains have a hard coat made of sporopollenin that protects the gametophytes during the process of their movement from the stamens to the pistil of flowering plants, or from the male cone to the female cone of gymnosperms. If pollen lands on a compatible pistil or female cone, it germinates, producing a pollen tube that transfers the sperm to the ovule containing the female gametophyte. Individual pollen grains are small enough to require magnification to see detail. The study of pollen is called palynology and is highly useful in paleoecology, paleontology, archaeology, and forensics. Pollen in plants is used for transferring haploid male genetic material from the anther of a single flower to the stigma of another in cross-pollination. In a case of self-pollination, this process takes place from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stylosanthes
''Stylosanthes'' is a genus of flowering plants in the legume family, Fabaceae and contains numerous highly important pasture and forage species. It was recently assigned to the informal monophyletic ''Pterocarpus'' clade of the Dalbergieae. The common name pencilflower is sometimes used for plants in this genus. Description The genus is characterised by trifoliate leaves and small yellow flowers Species may be annual or perennial and morphology varies between species as well as within species in response to grazing pressure. Some species such as '' S. scabra'' grow as a low woody shrub to 1.5 m, while others such as '' S. humilis'' will grow as a herbaceous shrub but can adopt a prostrate growth form and thrive under high grazing pressure. Taxonomy and range Taxonomy of the genus remains unsettled and controversial, with various authors favouring between 25 and 42 species, with at least 40 additional synonyms. The taxonomy is complicated by the existence of numerous natu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nepenthes
''Nepenthes'' () is a genus of carnivorous plants, also known as tropical pitcher plants, or monkey cups, in the monotypic family Nepenthaceae. The genus includes about 170 species, and numerous natural and many cultivated hybrids. They are mostly liana-forming plants of the Old World tropics, ranging from South China, Indonesia, Malaysia, and the Philippines; westward to Madagascar (two species) and the Seychelles (one); southward to Australia (four) and New Caledonia (one); and northward to India (one) and Sri Lanka (one). The greatest diversity occurs on Borneo, Sumatra, and the Philippines, with many endemic species. Many are plants of hot, humid, lowland areas, but the majority are tropical montane plants, receiving warm days but cool to cold, humid nights year round. A few are considered tropical alpine, with cool days and nights near freezing. The name "monkey cups" refers to the fact that monkeys were once thought to drink rainwater from the pitchers. Description ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drosera
''Drosera'', which is commonly known as the sundews, is one of the largest genera of carnivorous plants, with at least 194 species. 2 volumes. These members of the family Droseraceae lure, capture, and digest insects using stalked mucilaginous glands covering their leaf surfaces. The insects are used to supplement the poor mineral nutrition of the soil in which the plants grow. Various species, which vary greatly in size and form, are native to every continent except Antarctica.McPherson, S.R. 2008. ''Glistening Carnivores''. Redfern NaturalHistory Productions Ltd., Poole. Charles Darwin performed much of the early research into ''Drosera'', engaging in a long series of experiments with Drosera rotundifolia which were the first to confirm carnivory in plants. In an 1860 letter, Darwin wrote, “…at the present moment, I care more about ''Drosera'' than the origin of all the species in the world.” Both the botanical name (from the Greek δρόσος: ''drosos'' = "dew, d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tillandsia
''Tillandsia'' is a genus of around 650 species of evergreen, perennial flowering plants in the family Bromeliaceae, native to the forests, mountains and deserts of northern Mexico and south-eastern United States, Mesoamerica and the Caribbean to mid Argentina. Their leaves, more or less silvery in color, are covered with specialized cells (trichomes) capable of rapidly absorbing water that gathers on them. They are also commonly known as air plants because they are epiphytes, not needing soil for nourishment. They have a natural propensity to cling to whatever surfaces are readily available: telephone wires, tree branches, bark, bare rocks, etc. Their light seeds and a silky parachute facilitate their spread. Most ''Tillandsia'' species are epiphytes – which translates to 'upon a plant'. Some are aerophytes, which have a minimal root system and grow on shifting desert soil. Due to their epiphytic way of life, these plants will not grow in soil but live on the branches of tre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
