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Stinging Plant
A stinging plant or a plant with stinging hairs is a plant with hairs (trichomes) on its leaves or stems that are capable of injecting substances that cause pain or irritation. Other plants, such as opuntias, have hairs or spines that cause mechanical irritation, but do not inject chemicals. Stinging hairs occur particularly in the families Urticaceae, Loasaceae, Boraginaceae (subfamily Hydrophylloideae) and Euphorbiaceae. Such hairs have been shown to deter grazing mammals, but are no more effective against insect attack than non-stinging hairs. Many plants with stinging hairs have the word "nettle" in their English name, but may not be related to "true nettles" (the genus ''Urtica''). Though several unrelated families of plants have stinging hairs, their structure is generally similar. A solid base supports a single elongated cell with a brittle tip. When the tip is broken, the exposed sharp point penetrates the skin and pressure injects toxins. The precise chemicals involve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Urtica Dioica38 Ies
''Urtica'' is a genus of flowering plants in the family Urticaceae. Many species have stinging hairs and may be called nettles or stinging nettles (the latter name applying particularly to ''Urtica dioica, U. dioica''). The generic name ''Urtica'' derives from the Latin for 'sting'. Due to the stinging hairs, ''Urtica'' are rarely eaten by herbivores, but provide shelter for insects. The fiber has historically been used by humans, and cooking preparations exist. Description ''Urtica'' species grow as annual plant, annuals or perennial herbaceous plants, rarely shrubs. They can reach, depending on the type, location and nutrient status, a height of . The perennial species have underground rhizomes. The green parts have stinging hairs. Their often quadrangular stems are unbranched or branched, erect, ascending or spreading. Most leaves and stalks are arranged across Alternate leaf, opposite sides of the stem. The leaf blades are elliptic, lanceolate, ovate or circular. The leaf bl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silica
Silicon dioxide, also known as silica, is an oxide of silicon with the chemical formula , commonly found in nature as quartz. In many parts of the world, silica is the major constituent of sand. Silica is one of the most complex and abundant families of materials, existing as a compound of several minerals and as a synthetic product. Examples include fused quartz, fumed silica, opal, and aerogels. It is used in structural materials, microelectronics, and as components in the food and pharmaceutical industries. All forms are white or colorless, although impure samples can be colored. Silicon dioxide is a common fundamental constituent of glass. Structure In the majority of silicon dioxides, the silicon atom shows Tetrahedral molecular geometry, tetrahedral coordination, with four oxygen atoms surrounding a central Si atomsee 3-D Unit Cell. Thus, SiO2 forms 3-dimensional network solids in which each silicon atom is covalently bonded in a tetrahedral manner to 4 oxygen atoms. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neurotransmitter
A neurotransmitter is a signaling molecule secreted by a neuron to affect another cell across a Chemical synapse, synapse. The cell receiving the signal, or target cell, may be another neuron, but could also be a gland or muscle cell. Neurotransmitters are released from synaptic vesicles into the synaptic cleft where they are able to interact with neurotransmitter receptors on the target cell. Some neurotransmitters are also stored in large dense core vesicles. The neurotransmitter's effect on the target cell is determined by the receptor it binds to. Many neurotransmitters are synthesized from simple and plentiful precursors such as amino acids, which are readily available and often require a small number of biosynthetic steps for conversion. Neurotransmitters are essential to the function of complex neural systems. The exact number of unique neurotransmitters in humans is unknown, but more than 100 have been identified. Common neurotransmitters include Glutamate (neurotransmi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vertebrate
Vertebrates () are animals with a vertebral column (backbone or spine), and a cranium, or skull. The vertebral column surrounds and protects the spinal cord, while the cranium protects the brain. The vertebrates make up the subphylum Vertebrata with some 65,000 species, by far the largest ranked grouping in the phylum Chordata. The vertebrates include mammals, birds, amphibians, and various classes of fish and reptiles. The fish include the jawless Agnatha, and the jawed Gnathostomata. The jawed fish include both the Chondrichthyes, cartilaginous fish and the Osteichthyes, bony fish. Bony fish include the Sarcopterygii, lobe-finned fish, which gave rise to the tetrapods, the animals with four limbs. Despite their success, vertebrates still only make up less than five percent of all described animal species. The first vertebrates appeared in the Cambrian explosion some 518 million years ago. Jawed vertebrates evolved in the Ordovician, followed by bony fishes in the Devonian. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Laportea
''Laportea'' is a genus of plants in the family Urticaceae. They are herbaceous, either annual or perennial. Like many plants of the Urticaceae, they have stinging hairs. There are stinging and non-stinging hairs on the same plant. The genus was named after the French naturalist Francis de Laporte de Castelnau.Weddell, H. A. Chloris Andina. 1857''Essai d'une flore de la region alpine des Cordilleres de l'Amerique du Sud'' Vol. 1. Bertrand. Species , Kew's Plants of the World Online Plants of the World Online (POWO) is an online taxonomic database published by the Royal Botanic Gardens, Kew. History Following the Convention on Biological Diversity, the Royal Botanic Gardens in Kew launched Plants of the World Online i ... lists 36 species in the genus ''Laportea'': References * Urticaceae genera Taxa named by François-Louis Laporte, comte de Castelnau Taxonomy articles created by Polbot {{Urticaceae-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cnidoscolus Urens
''Cnidoscolus urens'' is a perennial, tropical American stinging herb of the family Euphorbiaceae, and is one of some 100 species belonging to the genus ''Cnidoscolus'' (from Gk. ''knidē'' "nettle", ''skōlos'' "thorn", and Latin ''urens'' "burning"). The plant is locally known as ''bull nettle'', ''spurge nettle'', ''bringamosa'' and ''mala mujer'' ("evil woman"). This species has an erect stem and is herbaceous when young, turning woody with age and from 50 to 150 centimeters tall. Leaves are lobed and large, while the white flowers occur in cymes, producing a spiny 3-seeded capsule with seeds rich in fats and proteins, resembling those of ''Ricinus communis''. Its carunculate seeds are usually dispersed by ants (myrmecochory) attracted by the edible elaiosome. The entire plant is covered in stinging hairs, and has a native range covering Central and South America, being found in Costa Rica, El Salvador, Guatemala, Honduras, Mexico, Nicaragua Nicaragua, officially the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Urtica Parviflora
''Urtica'' is a genus of flowering plants in the family Urticaceae. Many species have stinging hairs and may be called nettles or stinging nettles (the latter name applying particularly to '' U. dioica''). The generic name ''Urtica'' derives from the Latin for 'sting'. Due to the stinging hairs, ''Urtica'' are rarely eaten by herbivores, but provide shelter for insects. The fiber has historically been used by humans, and cooking preparations exist. Description ''Urtica'' species grow as annuals or perennial herbaceous plants, rarely shrubs. They can reach, depending on the type, location and nutrient status, a height of . The perennial species have underground rhizomes. The green parts have stinging hairs. Their often quadrangular stems are unbranched or branched, erect, ascending or spreading. Most leaves and stalks are arranged across opposite sides of the stem. The leaf blades are elliptic, lanceolate, ovate or circular. The leaf blades usually have three to five, rarely up ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Urtica Urens
''Urtica urens'', commonly known as annual nettle, dwarf nettle, small nettle, dog nettle, or burning nettle, is a herbaceous annual flowering plant species in the nettle family Urticaceae. It is native to Eurasia, including the Himalayan regions of Kalimpong, Darjeeling and Sikkim in India and can be found in North America, New Zealand and South Africa as an introduced species. It is reputed to sting more strongly than common nettle (''Urtica dioica''). Description Unlike the perennial and dioecious stinging nettle ''Urtica dioica'', ''Urtica urens'' is an annual plant, monoecious (with male and female flowers on the same plant) and generally much shorter. It can be distinguished from the stinging nettle by its more rounded leaves with coarser, deeper toothing and with the terminal tooth of similar length to the adjacent teeth. The lower leaves are shorter than their longer petioles and have stinging hairs only. Distribution The native distribution of ''Urtica urens'' includes m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Formic Acid
Formic acid (), systematically named methanoic acid, is the simplest carboxylic acid. It has the chemical formula HCOOH and structure . This acid is an important intermediate in chemical synthesis and occurs naturally, most notably in some ants. Esters, salts, and the anion derived from formic acid are called formates. Industrially, formic acid is produced from methanol. Natural occurrence Formic acid, which has a pungent, penetrating odor, is found naturally in insects, weeds, fruits and vegetables, and forest emissions. It appears in most ants and in stingless bees of the genus '' Oxytrigona''. Wood ants from the genus ''Formica'' can spray formic acid on their prey or to defend the nest. The puss moth caterpillar (''Cerura vinula'') will spray it as well when threatened by predators. It is also found in the trichomes of stinging nettle (''Urtica dioica''). Apart from that, this acid is incorporated in many fruits such as pineapple (0.21 mg per 100 g), apple (2 mg per ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Serotonin
Serotonin (), also known as 5-hydroxytryptamine (5-HT), is a monoamine neurotransmitter with a wide range of functions in both the central nervous system (CNS) and also peripheral tissues. It is involved in mood, cognition, reward, learning, memory, and physiological processes such as vomiting and vasoconstriction. In the CNS, serotonin regulates mood, appetite, and sleep. Most of the body's serotonin—about 90%—is synthesized in the gastrointestinal tract by enterochromaffin cells, where it regulates intestinal movements. It is also produced in smaller amounts in the brainstem's raphe nuclei, the skin's Merkel cells, pulmonary neuroendocrine cells, and taste receptor cells of the tongue. Once secreted, serotonin is taken up by platelets in the blood, which release it during clotting to promote vasoconstriction and platelet aggregation. Around 8% of the body's serotonin is stored in platelets, and 1–2% is found in the CNS. Serotonin acts as both a vasoconstrictor and vas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetylcholine
Acetylcholine (ACh) is an organic compound that functions in the brain and body of many types of animals (including humans) as a neurotransmitter. Its name is derived from its chemical structure: it is an ester of acetic acid and choline. Parts in the body that use or are affected by acetylcholine are referred to as cholinergic. Acetylcholine is the neurotransmitter used at the neuromuscular junction. In other words, it is the chemical that motor neurons of the nervous system release in order to activate muscles. This property means that drugs that affect cholinergic systems can have very dangerous effects ranging from paralysis to convulsions. Acetylcholine is also a neurotransmitter in the autonomic nervous system, both as an internal transmitter for both the sympathetic nervous system, sympathetic and the parasympathetic nervous system, and as the final product released by the parasympathetic nervous system. Acetylcholine is the primary neurotransmitter of the parasympathet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Histamine
Histamine is an organic nitrogenous compound involved in local immune responses communication, as well as regulating physiological functions in the gut and acting as a neurotransmitter for the brain, spinal cord, and uterus. Discovered in 1910, histamine has been considered a local hormone ( autocoid) because it is produced without involvement of the classic endocrine glands; however, in recent years, histamine has been recognized as a central neurotransmitter. Histamine is involved in the inflammatory response and has a central role as a mediator of itching. As part of an immune response to foreign pathogens, histamine is produced by basophils and by mast cells found in nearby connective tissues. Histamine increases the permeability of the capillaries to white blood cells and some proteins, to allow them to engage pathogens in the infected tissues. It consists of an imidazole ring attached to an ethylamine chain; under physiological conditions, the amino grou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
