26-412: (Not all are supported by molecular analyses. See tropicos query cited for more.) Dioscorea is a genus of over 600 species of flowering plants in the family Dioscoreaceae , native throughout the tropical and warm temperate regions of the world. The vast majority of the species are tropical, with only a few species extending into temperate climates. It was named by the monk Charles Plumier after
52-1855: A molecular phylogeny of plants placed the flowering plants in their evolutionary context: Bryophytes [REDACTED] Lycophytes [REDACTED] Ferns [REDACTED] [REDACTED] [REDACTED] The main groups of living angiosperms are: Amborellales [REDACTED] 1 sp. New Caledonia shrub Nymphaeales [REDACTED] c. 80 spp. water lilies & allies Austrobaileyales [REDACTED] c. 100 spp. woody plants Magnoliids [REDACTED] c. 10,000 spp. 3-part flowers, 1-pore pollen, usu. branch-veined leaves Chloranthales [REDACTED] 77 spp. Woody, apetalous Monocots [REDACTED] c. 70,000 spp. 3-part flowers, 1 cotyledon , 1-pore pollen, usu. parallel-veined leaves Ceratophyllales [REDACTED] c. 6 spp. aquatic plants Eudicots [REDACTED] c. 175,000 spp. 4- or 5-part flowers, 3-pore pollen, usu. branch-veined leaves Amborellales Melikyan, Bobrov & Zaytzeva 1999 Nymphaeales Salisbury ex von Berchtold & Presl 1820 Austrobaileyales Takhtajan ex Reveal 1992 Chloranthales Mart. 1835 Canellales Cronquist 1957 Piperales von Berchtold & Presl 1820 Magnoliales de Jussieu ex von Berchtold & Presl 1820 Laurales de Jussieu ex von Berchtold & Presl 1820 Acorales Link 1835 Alismatales Brown ex von Berchtold & Presl 1820 Petrosaviales Takhtajan 1997 Dioscoreales Brown 1835 Pandanales Brown ex von Berchtold & Presl 1820 Liliales Perleb 1826 Asparagales Link 1829 Arecales Bromhead 1840 Poales Small 1903 Zingiberales Grisebach 1854 Commelinales de Mirbel ex von Berchtold & Presl 1820 Mangyan Too Many Requests If you report this error to
78-447: A greenhouse setting, and once the shoots of the plants started "circumnutating," a pole was introduced to allow for twining around the object. Authors found that the amount of force being applied to the pole when the vine is twining is due to the stretching of the stipule. The forces of the bending and twisting motion of D. bulbifera did not generate a measurable force. In addition, this experiment indicates that stipules are not
104-610: A total of 64 angiosperm orders and 416 families. The diversity of flowering plants is not evenly distributed. Nearly all species belong to the eudicot (75%), monocot (23%), and magnoliid (2%) clades. The remaining five clades contain a little over 250 species in total; i.e. less than 0.1% of flowering plant diversity, divided among nine families. The 25 most species-rich of 443 families, containing over 166,000 species between them in their APG circumscriptions, are: The botanical term "angiosperm", from Greek words angeíon ( ἀγγεῖον 'bottle, vessel') and spérma ( σπέρμα 'seed'),
130-858: Is starting to impact plants and is likely to cause many species to become extinct by 2100. Angiosperms are terrestrial vascular plants; like the gymnosperms, they have roots , stems , leaves , and seeds . They differ from other seed plants in several ways. The largest angiosperms are Eucalyptus gum trees of Australia, and Shorea faguetiana , dipterocarp rainforest trees of Southeast Asia, both of which can reach almost 100 metres (330 ft) in height. The smallest are Wolffia duckweeds which float on freshwater, each plant less than 2 millimetres (0.08 in) across. Considering their method of obtaining energy, some 99% of flowering plants are photosynthetic autotrophs , deriving their energy from sunlight and using it to create molecules such as sugars . The remainder are parasitic , whether on fungi like
156-418: Is steroidal saponins , which can be converted through a series of chemical reactions into steroid hormones for use in medicine and as contraceptives. The 1889 book "The Useful Native Plants of Australia" records that Dioscorea hastifolia is "One of the hardiest of the yams. The tubers are largely consumed by the local aborigines for food. (Mueller)." Although the mechanism of Dioscorea vine behavior
182-538: Is maintained as distinct by others. For Dioscorea communis (L.) Caddick & Wilkin, see Tamus communis . Flowering plant Basal angiosperms Core angiosperms Flowering plants are plants that bear flowers and fruits , and form the clade Angiospermae ( / ˌ æ n dʒ i ə ˈ s p ər m iː / ). The term 'angiosperm' is derived from the Greek words ἀγγεῖον / angeion ('container, vessel') and σπέρμα / sperma ('seed'), meaning that
208-530: Is typically postponed until the relative stem has secured support. When leaf growth is delayed, shoot growth is hastened. Some vines produce an adhesive on their stems that contain calcium to better latch onto structures. A gradient is produced and the calcium exits cells to spread over stems. Furthermore, Dioscorea is a twiner, this means that the plant undergoes circumnutation which is a helical movement that allows stems to wrap around objects. In order for this mechanism to take place, endodermal cells, plasmodesmata,
234-409: Is unknown, it is likely that Dioscorea acts similarly to vines in terms of growth and movement behavior. Vines have a touch-sensitive component that allows them to locate and latch onto a supporting base. They use nearby plants, rocks, trees, and structures for physical support. Their touch receptors allow them to reach out and sense objects. Vines seek out these surfaces by sending out shoots to assess
260-491: The Alismatales grow in marine environments, spreading with rhizomes that grow through the mud in sheltered coastal waters. Some specialised angiosperms are able to flourish in extremely acid or alkaline habitats. The sundews , many of which live in nutrient-poor acid bogs , are carnivorous plants , able to derive nutrients such as nitrate from the bodies of trapped insects. Other flowers such as Gentiana verna ,
286-460: The orchids for part or all of their life-cycle, or on other plants , either wholly like the broomrapes, Orobanche , or partially like the witchweeds, Striga . In terms of their environment, flowering plants are cosmopolitan, occupying a wide range of habitats on land, in fresh water and in the sea. On land, they are the dominant plant group in every habitat except for frigid moss-lichen tundra and coniferous forest . The seagrasses in
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#1732781034638312-481: The seeds are enclosed within a fruit. The group was formerly called Magnoliophyta . Angiosperms are by far the most diverse group of land plants with 64 orders , 416 families , approximately 13,000 known genera and 300,000 known species . They include all forbs (flowering plants without a woody stem ), grasses and grass-like plants, a vast majority of broad-leaved trees , shrubs and vines , and most aquatic plants . Angiosperms are distinguished from
338-892: The "Big Five" extinction events in Earth's history, only the Cretaceous–Paleogene extinction event had occurred while angiosperms dominated plant life on the planet. Today, the Holocene extinction affects all kingdoms of complex life on Earth, and conservation measures are necessary to protect plants in their habitats in the wild ( in situ ), or failing that, ex situ in seed banks or artificial habitats like botanic gardens . Otherwise, around 40% of plant species may become extinct due to human actions such as habitat destruction , introduction of invasive species , unsustainable logging , land clearing and overharvesting of medicinal or ornamental plants . Further, climate change
364-408: The 1950s scientists found that the roots of wild yams contained diosgenin which is a plant-based estrogen; diosgenin is hypothesized to aid in chemical defense against herbivores. This was used to create the first birth control pills during the 60s. In addition, some Dioscorea species are rich in nutrients and antioxidants. This is beneficial in rural areas where the plant is native because it enriches
390-597: The Island of Mindoro in the Philippines , locally known as Karot/Nami ; Uses this type of tuber as an alternative of rice. Mangyan people typically soak it for 3 days, wash it in the running streams, dried for 2 days, and soak for 2 hours before cooking like a typical rice. The genus includes the following species and subspecies: The closely related genus Tamus is included in Dioscorea by some sources, but
416-469: The ancient Greek physician and botanist Dioscorides . Wild Yam ( Dioscorea ) is a vine that is invasive, deciduous, and herbaceous. This species is native to Asia, though, in the U.S., it is commonly found in Florida. They can grow over 18 metres (60 feet) in length. Wild yams are an important crop, as they have been used to prevent menstrual cramps, stomach cramps, and general pain for centuries. During
442-426: The area. This behavior is dependent on the species, but these shoots typically move in a clockwise or counterclockwise direction, induced by circadian rhythms. When the vine makes contact with an object, the tendril shoot will coil around the object; this is a reaction called thigmotropism . This tendril can control the amount of tension and squeeze the object to stay attached to it and prevent falling. Leaf growth
468-627: The diets of individuals who live in the area. These plants grow best near canopy gaps in woodlands and rainforests. Dioscorea uses vining behavior which is useful in tropical habitats because Dioscorea grow under canopies and need to latch onto different surfaces in order to grow upwards and acquire resources. Several species, known as yams , are important agricultural crops in tropical regions, grown for their large tubers. Many of these are toxic when fresh, but can be detoxified and eaten, and are particularly important in parts of Africa , Asia , and Oceania . One class of toxins found in many species
494-818: The dominant group of plants across the planet. Agriculture is almost entirely dependent on angiosperms, and a small number of flowering plant families supply nearly all plant-based food and livestock feed. Rice , maize and wheat provide half of the world's staple calorie intake, and all three plants are cereals from the Poaceae family (colloquially known as grasses). Other families provide important industrial plant products such as wood , paper and cotton , and supply numerous ingredients for beverages , sugar production , traditional medicine and modern pharmaceuticals . Flowering plants are also commonly grown for decorative purposes , with certain flowers playing significant cultural roles in many societies. Out of
520-659: The flowering plants as an unranked clade without a formal Latin name (angiosperms). A formal classification was published alongside the 2009 revision in which the flowering plants rank as the subclass Magnoliidae. From 1998, the Angiosperm Phylogeny Group (APG) has reclassified the angiosperms, with updates in the APG II system in 2003, the APG III system in 2009, and the APG IV system in 2016. In 2019,
546-518: The manner of vines or lianas . The number of species of flowering plants is estimated to be in the range of 250,000 to 400,000. This compares to around 12,000 species of moss and 11,000 species of pteridophytes . The APG system seeks to determine the number of families , mostly by molecular phylogenetics . In the 2009 APG III there were 415 families. The 2016 APG IV added five new orders (Boraginales, Dilleniales, Icacinales, Metteniusales and Vahliales), along with some new families, for
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#1732781034638572-447: The only driving force for tension in vines and that they contribute to increased squeezing force later in development. Overall, Dioscorea has a vining mechanism that allows it to obtain nutrients while living under a canopy; it has evolved to do this by seeking out surfaces to climb and latch onto. Vines, like Dioscorea , have touch-sensitive components that allow them to specialize in this behavior. The Alangan Tribe of Mangyan in
598-567: The other major seed plant clade, the gymnosperms , by having flowers , xylem consisting of vessel elements instead of tracheids , endosperm within their seeds, and fruits that completely envelop the seeds. The ancestors of flowering plants diverged from the common ancestor of all living gymnosperms before the end of the Carboniferous , over 300 million years ago. In the Cretaceous , angiosperms diversified explosively , becoming
624-403: The plasma membrane, epidermal cells, calcium, potassium, chloride, and proton pumps are required. The SCR gene is also crucial for twining to occur. In 2009, an experiment was conducted to address the mechanism of force generation in the twining plant, Dioscorea bulbifera . To do this, the authors used a mechanical pole that measured the squeezing force of the twining vine. Plants were grown in
650-568: The spring gentian, are adapted to the alkaline conditions found on calcium -rich chalk and limestone , which give rise to often dry topographies such as limestone pavement . As for their growth habit , the flowering plants range from small, soft herbaceous plants , often living as annuals or biennials that set seed and die after one growing season, to large perennial woody trees that may live for many centuries and grow to many metres in height. Some species grow tall without being self-supporting like trees by climbing on other plants in
676-483: Was coined in the form "Angiospermae" by Paul Hermann in 1690, including only flowering plants whose seeds were enclosed in capsules. The term angiosperm fundamentally changed in meaning in 1827 with Robert Brown , when angiosperm came to mean a seed plant with enclosed ovules. In 1851, with Wilhelm Hofmeister 's work on embryo-sacs, Angiosperm came to have its modern meaning of all the flowering plants including Dicotyledons and Monocotyledons. The APG system treats
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