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Phototrope
In biology, phototropism is the growth of an organism in response to a light stimulus. Phototropism is most often observed in plants, but can also occur in other organisms such as fungi. The cells on the plant that are farthest from the light contain a hormone called auxin that reacts when phototropism occurs. This causes the plant to have elongated cells on the furthest side from the light. Phototropism is one of the many plant tropisms, or movements, which respond to external stimuli. Growth towards a light source is called positive phototropism, while growth away from light is called negative phototropism. Negative phototropism is not to be confused with skototropism, which is defined as the growth towards darkness, whereas negative phototropism can refer to either the growth away from a light source or towards the darkness. Most plant shoots exhibit positive phototropism, and rearrange their chloroplasts in the leaves to maximize photosynthetic energy and promote growth.Goy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coleoptile
Coleoptile is the pointed protective sheath covering the emerging shoot in monocotyledons such as grasses in which few leaf primordia and shoot apex of monocot embryo remain enclosed. The coleoptile protects the first leaf as well as the growing stem in seedlings and eventually, allows the first leaf to emerge. Coleoptiles have two vascular bundles, one on either side. Unlike the flag leaves rolled up within, the pre-emergent coleoptile does not accumulate significant protochlorophyll or carotenoids, and so it is generally very pale. Some preemergent coleoptiles do, however, accumulate purple anthocyanin pigments. Coleoptiles consist of very similar cells that are all specialised to fast stretch growth. They do not divide, but increase in size as they accumulate more water. Coleoptiles also have water vessels (frequently two) along the axis to provide a water supply. When a coleoptile reaches the surface, it stops growing and the flag leaves penetrate its top, continuing to grow ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ravenala
''Ravenala'' is a genus of monocotyledonous flowering plants. Classically, the genus was considered to include a single species, ''Ravenala madagascariensis'' from Madagascar. Taxonomy Species of the genus ''Ravenala'' are not true palms (family Arecaceae) but members of the family Strelitziaceae. The genus is closely related to the southern African genus '' Strelitzia'' and the South American genus '' Phenakospermum''. Some older classifications include these genera in the banana family (Musaceae). Etymology The scientific name ''Ravenala'' comes from Malagasy ''ravinala'' or ''ravina ala'' meaning "forest leaves". Species Although formerly considered to be monotypic, four different forms have been distinguished. Five new species were described in 2021, all from Madagascar. The following species are currently recognised in the genus ''Ravenala'': *'' Ravenala agatheae'' *'' Ravenala blancii'' *'' Ravenala grandis'' *'' Ravenala hladikorum'' *''Ravenala madagascariensis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Azuki Bean
''Vigna angularis'', also known as the , azuki bean, aduki bean, red bean, or red mung bean, is an annual vine widely cultivated throughout East Asia for its small (approximately long) bean. The cultivars most familiar in East Asia have a uniform red color, but there are white, black, gray, and variously mottled varieties. Scientists presume ''Vigna angularis'' var. ''nipponensis'' is the progenitor. Origin and diversity Speciation and domestication The wild ancestor of cultivated adzuki bean is probably ''Vigna angularis'' var. ''nipponensis'', which is distributed across East Asia. Speciation between ''Vigna angularis'' var. ''nipponensis'' and ''Vigna angularis'' var. ''angularis'' occurred around years ago. Wild adzuki likely originated near the Himalayas and spread naturally to central China and Japan. Archaeologists estimate it was domesticated around 3000 BC. However, adzuki beans, as well as soybeans, dating from 3000 BC to 2000 BC are indicated to still be la ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phalaenopsis
''Phalaenopsis'' (), also known as moth orchids, is a genus of about seventy species of plants in the family Orchidaceae. Orchids in this genus are monopodial epiphytes or lithophytes with long, coarse roots, short, leafy stems and long-lasting, flat flowers arranged in a flowering stem that often branches near the end. Orchids in this genus are native to Asia, New Guinea, and Australia, but mostly occur in Indonesia and the Philippines. Description Orchids in the genus ''Phalaenopsis'' are monopodial epiphytic, sometimes lithophytic herbs with long, coarse roots with pneumatodes (which allow for gaseous exchange of the photosynthetic roots), and short leafy stems hidden by overlapping leaf bases. The leaves are usually arranged in two rows, relatively large and leathery, oblong to elliptic and sometimes succulent. A few to many, small to large, long-lasting, flat, often fragrant flowers are arranged on erect to hanging racemes or panicles. The sepals and petals are fre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phycomyces
''Phycomyces'' is a genus of fungus in the Mucoromycota phylum. They are known for their strong phototropism response and helical growth of the sporangium. The best studied species is '' Phycomyces blakesleeanus''. Asexual reproduction ''Phycomyces'' can reproduce via extension of mycelia, or by production of spores either asexually or sexually. The asexual cycle includes the formation of spore containing sporangia borne on the top of sporangiophores that may extend 10 to 15 cm above the surface of the fungal colony from which they emerged. The long filamentous sporangiophores respond to divergent environmental signals including light, gravity, wind, chemicals, and adjacent objects. The sporangia contain vegetative spores with one to six haploid nuclei. When these spores are dispersed, they can establish new colonies. Sexual reproduction ''Phycomyces'' have two mating types that are indistinguishable morphologically. The sexual cycle is thought to occur by the followin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cryptochrome
Cryptochromes (from the Greek κρυπτός χρώμα, "hidden colour") are a class of flavoproteins found in plants and animals that are sensitive to blue light. They are involved in the circadian rhythms and the sensing of magnetic fields in a number of species. The name ''cryptochrome'' was proposed as a ''portmanteau'' combining the '' chromatic'' nature of the photoreceptor, and the '' cryptogamic'' organisms on which many blue-light studies were carried out. The genes ''CRY1'' and ''CRY2'' encode the proteins CRY1 and CRY2, respectively. Cryptochromes are classified into plant Cry and animal Cry. Animal Cry can be further categorized into insect type (Type I) and mammal-like (Type II). CRY1 is a circadian photoreceptor whereas CRY2 is a clock repressor which represses Clock/Cycle (Bmal1) complex in insects and vertebrates. In plants, blue-light photoreception can be used to cue developmental signals. Besides chlorophylls, cryptochromes are the only proteins known ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phytochrome
Phytochromes are a class of photoreceptor proteins found in plants, bacteria and fungi. They respond to light in the red and far-red regions of the visible spectrum and can be classed as either Type I, which are activated by far-red light, or Type II that are activated by red light. Recent advances have suggested that phytochromes also act as temperature sensors, as warmer temperatures enhance their de-activation. All of these factors contribute to the plant's ability to germinate. Phytochromes control many aspects of plant development. They regulate the germination of seeds (photoblasty), the synthesis of chlorophyll, the elongation of seedlings, the size, shape and number and movement of leaves and the timing of flowering in adult plants. Phytochromes are widely expressed across many tissues and developmental stages. Other plant photoreceptors include cryptochromes and phototropins, which respond to blue and ultraviolet-A light and UVR8, which is sensitive to ultraviol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phototropin
Phototropins are blue light photoreceptor proteins (more specifically, flavoproteins) that mediate phototropism responses across many species of algae, fungi and higher plants. Phototropins can be found throughout the leaves of a plant. Along with cryptochromes and phytochromes they allow plants to respond and alter their growth in response to the light environment. When phototropins are hit with blue light, they induce a signal transduction pathway that alters the plant cells' functions in different ways. Phototropins are part of the phototropic sensory system in plants that causes various environmental responses in plants. Phototropins specifically will cause stems to bend towards light and stomata to open. In addition phototropins mediate the first changes in stem elongation in blue light prior to cryptochrome activation. Phototropins are also required for blue light mediated transcript destabilization of specific mRNAs in the cell. Phototropins also regulate the movement of c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basipetal
This glossary of mycology is a list of definitions of terms and concepts relevant to mycology, the study of fungi. Terms in common with other fields, if repeated here, generally focus on their mycology-specific meaning. Related terms can be found in glossary of biology and glossary of botany, among others. List of Latin and Greek words commonly used in systematic names and Botanical Latin may also be relevant, although some prefixes and suffixes very common in mycology are repeated here for clarity. A B C D E F ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Model For Auxin Transport
A model is an informative representation of an object, person, or system. The term originally denoted the Plan_(drawing), plans of a building in late 16th-century English, and derived via French language, French and Italian language, Italian ultimately from Latin , . Models can be divided into physical models (e.g. a ship model or a fashion model) and abstract models (e.g. a Numerical weather prediction, set of mathematical equations describing the workings of the atmosphere for the purpose of weather forecasting). Abstract or conceptual models are central to philosophy of science. In scholarly research and applied science, a model should not be confused with a theory: while a model seeks only to represent reality with the purpose of better understanding or predicting the world, a theory is more ambitious in that it claims to be an explanation of reality. Types of model ''Model'' in specific contexts As a noun, ''model'' has specific meanings in certain fields, derived from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arabidopsis Thaliana
''Arabidopsis thaliana'', the thale cress, mouse-ear cress or arabidopsis, is a small plant from the mustard family (Brassicaceae), native to Eurasia and Africa. Commonly found along the shoulders of roads and in disturbed land, it is generally considered a weed. A winter annual with a relatively short lifecycle, ''A. thaliana'' is a popular model organism in plant biology and genetics. For a complex multicellular eukaryote, ''A. thaliana'' has a relatively small genome of around 135 Base pair#Length measurements, megabase pairs. It was the first plant to have its genome sequenced, and is an important tool for understanding the molecular biology of many plant traits, including flower development and phototropism, light sensing. Description ''Arabidopsis thaliana'' is an annual plant, annual (rarely biennial plant, biennial) plant, usually growing to 20–25 cm tall. The leaf, leaves form a rosette at the base of the plant, with a few leaves also on the flowering Plant ste ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
