Petiolar
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Petiolar
In botany, the petiole () is the stalk that attaches the leaf blade to the stem, and is able to twist the leaf to face the sun. This gives a characteristic foliage arrangement to the plant. Outgrowths appearing on each side of the petiole in some species are called stipules. Leaves with a petiole are said to be petiolate, while leaves lacking a petiole are called sessile or apetiolate. Description The petiole is a stalk that attaches a leaf to the plant stem. In petiolate leaves, the leaf stalk may be long, as in the leaves of celery and rhubarb, or short. When completely absent, the blade attaches directly to the stem and is said to be sessile. Subpetiolate leaves have an extremely short petiole, and may appear sessile. The broomrape family Orobanchaceae is an example of a family in which the leaves are always sessile. In some other plant groups, such as the speedwell genus '' Veronica'', petiolate and sessile leaves may occur in different species. In the grasses (Poaceae), ...
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Leaf
A leaf ( : leaves) is any of the principal appendages of a vascular plant stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, stem, flower, and fruit collectively form the shoot system. In most leaves, the primary photosynthetic tissue is the palisade mesophyll and is located on the upper side of the blade or lamina of the leaf but in some species, including the mature foliage of ''Eucalyptus'', palisade mesophyll is present on both sides and the leaves are said to be isobilateral. Most leaves are flattened and have distinct upper (adaxial) and lower ( abaxial) surfaces that differ in color, hairiness, the number of stomata (pores that intake and output gases), the amount and structure of epicuticular wax and other features. Leaves are mostly green in color due to the presence of a compound called chlorophyll that is essential for photosynthesis as it absorbs light ...
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Leaf
A leaf ( : leaves) is any of the principal appendages of a vascular plant stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, stem, flower, and fruit collectively form the shoot system. In most leaves, the primary photosynthetic tissue is the palisade mesophyll and is located on the upper side of the blade or lamina of the leaf but in some species, including the mature foliage of ''Eucalyptus'', palisade mesophyll is present on both sides and the leaves are said to be isobilateral. Most leaves are flattened and have distinct upper (adaxial) and lower ( abaxial) surfaces that differ in color, hairiness, the number of stomata (pores that intake and output gases), the amount and structure of epicuticular wax and other features. Leaves are mostly green in color due to the presence of a compound called chlorophyll that is essential for photosynthesis as it absorbs light ...
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Stipule
In botany, a stipule is an outgrowth typically borne on both sides (sometimes on just one side) of the base of a leafstalk (the petiole). Stipules are considered part of the anatomy of the leaf of a typical flowering plant, although in many species they may be inconspicuous —or sometimes entirely absent, and the leaf is then termed ''exstipulate''. (In some older botanical writing, the term "stipule" was used more generally to refer to any small leaves or leaf-parts, notably prophylls.) The word ''stipule'' was coined by Linnaeus''Concise English Dictionary'' Wordsworth Editions Ltd. 1994, from Latin ''stipula'', straw, stalk. Types of stipules General characteristics The position of stipules on a plant varies widely from species to species, though they are often located near the base of a leaf. Stipules are most common on dicotyledons, where they appear in pairs alongside each leaf. Some monocotyledon plants display stipule-like structures, but only display one per leaf ...
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Hymenoptera
Hymenoptera is a large order (biology), order of insects, comprising the sawfly, sawflies, wasps, bees, and ants. Over 150,000 living species of Hymenoptera have been described, in addition to over 2,000 extinct ones. Many of the species are Parasitoid wasp, parasitic. Females typically have a special ovipositor for inserting eggs into hosts or places that are otherwise inaccessible. This ovipositor is often modified into a stinger. The young develop through holometabolism (complete metamorphosis (biology), metamorphosis)—that is, they have a wormlike larval stage and an inactive pupal stage before they mature. Etymology The name Hymenoptera refers to the wings of the insects, but the original derivation is ambiguous. All references agree that the derivation involves the Ancient Greek language, Ancient Greek wikt:πτερόν, πτερόν (''pteron'') for wing. The Ancient Greek wikt:ὑμήν, ὑμήν (''hymen'') for membrane provides a plausible etymology for the term bec ...
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Apium Graveolens
Celery (''Apium graveolens'') is a marshland plant in the family Apiaceae that has been cultivated as a vegetable since antiquity. Celery has a long fibrous stalk tapering into leaves. Depending on location and cultivar, either its stalks, leaves or hypocotyl are eaten and used in cooking. Celery seed powder is used as a spice. Description Celery leaves are pinnate to bipinnate with rhombic leaflets long and broad. The flowers are creamy-white, in diameter, and are produced in dense compound umbels. The seeds are broad ovoid to globose, long and wide. Modern cultivars have been selected for either solid petioles, leaf stalks, or a large hypocotyl. A celery stalk readily separates into "strings" which are bundles of angular collenchyma cells exterior to the vascular bundles. Wild celery, ''Apium graveolens'' var. ''graveolens'', grows to tall. Celery is a biennial plant that occurs around the globe. It produces flowers and seeds only during its second year. The first cul ...
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Acacia
''Acacia'', commonly known as the wattles or acacias, is a large genus of shrubs and trees in the subfamily Mimosoideae of the pea family Fabaceae. Initially, it comprised a group of plant species native to Africa and Australasia. The genus name is New Latin, borrowed from the Greek (), a term used by Dioscorides for a preparation extracted from the leaves and fruit pods of ''Vachellia nilotica'', the original type of the genus. In his ''Pinax'' (1623), Gaspard Bauhin mentioned the Greek from Dioscorides as the origin of the Latin name. In the early 2000s it had become evident that the genus as it stood was not monophyletic and that several divergent lineages needed to be placed in separate genera. It turned out that one lineage comprising over 900 species mainly native to Australia, New Guinea, and Indonesia was not closely related to the much smaller group of African lineage that contained ''A. nilotica''—the type species. This meant that the Australasian lineage (by ...
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Acacia Koa
''Acacia koa'' or commonly known as koa is a species of flowering tree in the family Fabaceae. It is endemic to the Hawaiian Islands, where it is the second most common tree. The highest populations are on Hawaii, Maui and Oahu. Name The name ''koa'' in the Hawaiian language ultimately comes from Proto-Austronesian *''teRas'' meaning "core" or "ironwood"; many names referring to certain ironwood or heartwood species in Southeast Asia and Oceania such as ''Vitex parviflora'' (''tugás'' in Cebuano), ''Eusideroxylon zwageri'' (''togas'' in Tombonuwo), and ''Intsia bijuga'' (''dort'' in Palauan) descend from this root. ''Koa'' also means brave, bold, fearless, or warrior. Description Koa is a large tree, typically attaining a height of and a spread of . In deep volcanic ash, a koa tree can reach a height of , a circumference of , and a spread of . It is one of the fastest-growing Hawaiian trees, capable of reaching in five years on a good site. Leaves Initially, bipinnat ...
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Hydrophyte
Aquatic plants are plants that have adapted to living in aquatic environments (saltwater or freshwater). They are also referred to as hydrophytes or macrophytes to distinguish them from algae and other microphytes. A macrophyte is a plant that grows in or near water and is either emergent, submergent, or floating. In lakes and rivers macrophytes provide cover for fish, substrate for aquatic invertebrates, produce oxygen, and act as food for some fish and wildlife. Macrophytes are primary producers and are the basis of the food web for many organisms. They have a significant effect on soil chemistry and light levels as they slow down the flow of water and capture pollutants and trap sediments. Excess sediment will settle into the benthos aided by the reduction of flow rates caused by the presence of plant stems, leaves and roots. Some plants have the capability of absorbing pollutants into their tissue. Seaweeds are multicellular marine algae and, although their ecological i ...
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Rheum Rhabarbarum
''Rheum rhabarbarum'' is a species of flowering plant in the family Polygonaceae, native to a region stretching from southern Siberia to north and central China. It has been harvested from the wild for centuries for its root, which was harvested for use as a popular medicine in Europe and Asia. It was later cultivated for its root in England and Russia. It is considered to be one of the species involved in the development of culinary rhubarb, for which the scientific name ''R. rhabarbarum'' is sometimes (erroneously) used. Taxonomy ''Rheum rhabarbarum'' was first described by Carl Linnaeus in 1753. Linnaeus also described ''R. undulatum'', but this is now considered to be the same species. The name ''rha barbarum'', Latin for 'foreign rha', was first used in the writings of Celsus, who uses the word to describe a valued medicinal root imported from the east. Description Similar species According to the 2003 key in the ''Flora of China'', this species is distinguished f ...
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Cardoons
The cardoon, ''Cynara cardunculus'' (), also called the artichoke thistle, is a thistle in the family Asteraceae. It is a naturally occurring species that also has many cultivated forms, including the globe artichoke. It is native to the western and central Mediterranean region, where it was domesticated in ancient times and still occurs as a wild plant. Description The wild cardoon is a stout herbaceous perennial plant growing tall, with deeply lobed and heavily spined green to grey-green tomentose (hairy or downy) leaves up to long, with yellow spines up to 3.5 cm long. The flowers are violet-purple, produced in a large, globose, massively spined capitulum up to in diameter.Tela Botanica: ''Cynara cardunculus'' L.
(in French)
Huxley, A., ed. (1992). ''New RHS Diction ...
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Artichokes
The globe artichoke (''Cynara cardunculus'' var. ''scolymus'' ),Rottenberg, A., and D. Zohary, 1996: "The wild ancestry of the cultivated artichoke." Genet. Res. Crop Evol. 43, 53–58. also known by the names French artichoke and green artichoke in the U.S., is a variety of a species of thistle cultivated as food. The edible portion of the plant consists of the flower buds before the flowers come into bloom. The budding artichoke flower-head is a cluster of many budding small flowers (an inflorescence), together with many bracts, on an edible base. Once the buds bloom, the structure changes to a coarse, barely edible form. Another variety of the same species is the cardoon, a perennial plant native to the Mediterranean region. Both wild forms and cultivated varieties (cultivars) exist. Description This vegetable grows to tall, with arching, deeply lobed, silvery, glaucous-green leaves long. The flowers develop in a large head from an edible bud about diameter with numerous ...
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Marantaceae
The Marantaceae are a family, the arrowroot family, of flowering plants consisting of 31 genera and around 530 species, defining it as one of the most species-rich families in its order.Kennedy, H. (2000). “Diversification in pollination mechanisms in the Marantaceae”. Pp. 335-343 in Monocots: systematics and evolution, eds. K. L. Wilson and D. A. Morrison. Melbourne: CSIROLey, A. C., and Claßen-Bockhoff, R. (2011). “Evolution in African Marantaceae - evidence from phylogenetic, ecological and morphological studies”. Syst. Bot. 36, 277–290. doi: 10.1600/036364411X569480 Species of this family are found in lowland tropical forests of Africa, Asia, and the Americas. The majority (80%) of the species are found in the American tropics, followed by Asian (11%) and African (9%) tropics. They are commonly called the prayer-plant family and are also known for their unique secondary pollination presentation. Description The plants usually have underground rhizomes or tubers. The ...
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