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Pentoxylon
Pentoxylales is an extinct order of seed plants known from the Jurassic and Early Cretaceous of East Gondwana. Discovery The first specimens belonging to Pentoxylales were reported by Birbal Sahni in 1948 from Jurassic-Cretaceous strata of the Rajmahal Hills of northeastern India. Remains have subsequently been reported from New Zealand, Australia and Antarctica. The oldest records of the group date to the Upper Jurassic, though there are unconfirmed Early Jurassic records. Morphology Stem The stem of Pentoxylales, referred to by the morphogenus '' Pentoxylon'', consists of 5 or 6 wedge shaped segments embedded within thin walled ground tissue. Leaves Leaves of Pentoxylales are of the strap shaped '' Taenopteris'' morphotype shared with other groups of seed plants, while leaves that preserve the cuticle are referred to the morphogenus '' Nipaniophyllum.'' The leaves are up to 20 centimetres long, and have a prominent midrib. Pollen organs The pollen organs of Pen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pentoxylon
Pentoxylales is an extinct order of seed plants known from the Jurassic and Early Cretaceous of East Gondwana. Discovery The first specimens belonging to Pentoxylales were reported by Birbal Sahni in 1948 from Jurassic-Cretaceous strata of the Rajmahal Hills of northeastern India. Remains have subsequently been reported from New Zealand, Australia and Antarctica. The oldest records of the group date to the Upper Jurassic, though there are unconfirmed Early Jurassic records. Morphology Stem The stem of Pentoxylales, referred to by the morphogenus '' Pentoxylon'', consists of 5 or 6 wedge shaped segments embedded within thin walled ground tissue. Leaves Leaves of Pentoxylales are of the strap shaped '' Taenopteris'' morphotype shared with other groups of seed plants, while leaves that preserve the cuticle are referred to the morphogenus '' Nipaniophyllum.'' The leaves are up to 20 centimetres long, and have a prominent midrib. Pollen organs The pollen organs of Pen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peduncle (botany)
In botany, a peduncle is a stalk supporting an inflorescence or a solitary flower, or, after fecundation, an infructescence or a solitary fruit. The peduncle sometimes has bracts (a type of cataphylls) at nodes. The main axis of an inflorescence above the peduncle is the rachis. There are no flowers on the peduncle but there are flowers on the rachis. When a peduncle arises from the ground level, either from a compressed aerial stem or from a subterranean stem ( rhizome, tuber, bulb, corm A corm, bulbo-tuber, or bulbotuber is a short, vertical, swollen underground plant stem that serves as a storage organ that some plants use to survive winter or other adverse conditions such as summer drought and heat (perennation). The word ' ...), with few or no bracts except the part near the rachis or receptacle, it is referred to as a scape. The acorns of the pedunculate oak are borne on a long peduncle, hence the name of the tree. See also * Pedicel (botany) * Scape (botany ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prehistoric Plant Orders
Prehistory, also known as pre-literary history, is the period of human history between the use of the first stone tools by hominins 3.3 million years ago and the beginning of recorded history with the invention of writing systems. The use of symbols, marks, and images appears very early among humans, but the earliest known writing systems appeared 5000 years ago. It took thousands of years for writing systems to be widely adopted, with writing spreading to almost all cultures by the 19th century. The end of prehistory therefore came at very different times in different places, and the term is less often used in discussing societies where prehistory ended relatively recently. In the early Bronze Age, Sumer in Mesopotamia, the Indus Valley Civilisation, and ancient Egypt were the first civilizations to develop their own scripts and to keep historical records, with their neighbors following. Most other civilizations reached the end of prehistory during the following Iron Age. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bennettitales
Bennettitales (also known as cycadeoids) is an extinct order of seed plants that first appeared in the Permian period and became extinct in most areas toward the end of the Cretaceous. Bennettitales are among the most common Mesozoic seed plants, and had morphologies including shrub and cycad-like forms. The foliage of bennettitaleans is superficially nearly indistinguishable from that of cycads, but they are distinguished from cycads by their more complex flower-like reproductive organs, at least some of which were likely pollinated by insects. Although certainly gymnosperms (cone-bearing seed plants), the relationships of bennettitaleans to other seed plants is debated. Their general resemblance to cycads is contradicted by numerous more subtle features of their reproductive systems and leaf structure. Some authors have linked bennettitaleans to angiosperms (flowering plants) and gnetophytes (a rare and unusual group of modern gymnosperms), forming a broader group known as Ant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glossopteris
''Glossopteris'' tymology: from Ancient Greek γλῶσσα (glôssa, " tongue ") + πτερίς (pterís, " fern ")is the largest and best-known genus of the extinct Permian order of seed ferns known as Glossopteridales (also known as Arberiales, Ottokariales, or Dictyopteridiales). The genus ''Glossopteris'' refers only to leaves, within a framework of form genera used in paleobotany. (For likely reproductive organs see Glossopteridaceae.) Species of ''Glossopteris'' were the dominant trees of the middle- to high-latitude lowland vegetation across the supercontinent Gondwana during the Permian Period. ''Glossopteris'' fossils were critical in recognizing former connections between the various fragments of Gondwana: South America, Africa, India, Australia, New Zealand, and Antarctica. History The Glossopteridales arose in the Southern Hemisphere around the beginning of the Permian Period (), but became extinct during the end-Permian (Changhsingian) mass extinction. The puta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bramble
A bramble is any rough, tangled, prickly shrub, usually in the genus ''Rubus'', which grows blackberries, raspberries, or dewberries. "Bramble" is also used to describe other prickly shrubs, such as roses (''Rosa'' species). The fruits include blackberries, arctic brambleberries, or raspberries, depending on the species, and are used to make jellies, jams, and preserves. In British English, bramble usually refers to the common blackberry, ''Rubus fruticosus''. ''R. fruticosus'' grows abundantly in all parts of the British Isles, and harvesting the fruits in late summer and autumn is often considered a favourite pastime. An especially hardy plant, bramble bushes can also become a nuisance in gardens, sending down strong suckering roots amongst hedges and shrubs and being particularly resilient against pruning. Many consider ''R. fruticosus'' a weed due its tendency to grow in neglected areas and its sharp, tough thorns, which can be hazardous to children and pets. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Liana
A liana is a long- stemmed, woody vine that is rooted in the soil at ground level and uses trees, as well as other means of vertical support, to climb up to the canopy in search of direct sunlight. The word ''liana'' does not refer to a taxonomic grouping, but rather a habit of plant growth – much like '' tree'' or '' shrub''. It comes from standard French ''liane'', itself from an Antilles French dialect word meaning to sheave. Ecology Lianas are characteristic of tropical moist broadleaf forests (especially seasonal forests), but may be found in temperate rainforests and temperate deciduous forests. There are also temperate lianas, for example the members of the '' Clematis'' or '' Vitis'' (wild grape) genera. Lianas can form bridges amidst the forest canopy, providing arboreal animals with paths across the forest. These bridges can protect weaker trees from strong winds. Lianas compete with forest trees for sunlight, water and nutrients from the soil. Forests wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tree
In botany, a tree is a perennial plant with an elongated stem, or trunk, usually supporting branches and leaves. In some usages, the definition of a tree may be narrower, including only woody plants with secondary growth, plants that are usable as lumber or plants above a specified height. In wider definitions, the taller palms, tree ferns, bananas, and bamboos are also trees. Trees are not a taxonomic group but include a variety of plant species that have independently evolved a trunk and branches as a way to tower above other plants to compete for sunlight. The majority of tree species are angiosperms or hardwoods; of the rest, many are gymnosperms or softwoods. Trees tend to be long-lived, some reaching several thousand years old. Trees have been in existence for 370 million years. It is estimated that there are some three trillion mature trees in the world. A tree typically has many secondary branches supported clear of the ground by the trunk. This trunk typicall ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Habit (biology)
Habit, equivalent to habitus in some applications in biology, refers variously to aspects of behaviour or structure, as follows: *In zoology (particularly in ethology), habit usually refers to aspects of more or less predictable ''behaviour'', instinctive or otherwise, though it also has broader application. Habitus refers to the characteristic form or morphology of a species. *In botany, habit is the characteristic form in which a given species of plant grows (see plant habit).Jackson, Benjamin, Daydon; A Glossary of Botanic Terms with their Derivation and Accent; Published by Gerald Duckworth & Co. London, 4th ed 1928 Behavior In zoology, ''habit'' (not to be confused with ''habitus'' as described below) usually refers to a specific behavior pattern, either adopted, learned, pathological, innate, or directly related to physiology. For example: * ...the atwas in the ''habit'' of springing upon the oor knockerin order to gain admission... * If these sensitive parrots are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flower
A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants (plants of the division Angiospermae). The biological function of a flower is to facilitate reproduction, usually by providing a mechanism for the union of sperm with eggs. Flowers may facilitate outcrossing (fusion of sperm and eggs from different individuals in a population) resulting from cross-pollination or allow selfing (fusion of sperm and egg from the same flower) when self-pollination occurs. There are two types of pollination: self-pollination and cross-pollination. Self-pollination occurs when the pollen from the anther is deposited on the stigma of the same flower, or another flower on the same plant. Cross-pollination is when pollen is transferred from the anther of one flower to the stigma of another flower on a different individual of the same species. Self-pollination happens in flowers where the stamen and carpel mature at the same time, and are posi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fruit
In botany, a fruit is the seed-bearing structure in flowering plants that is formed from the ovary after flowering. Fruits are the means by which flowering plants (also known as angiosperms) disseminate their seeds. Edible fruits in particular have long propagated using the movements of humans and animals in a symbiotic relationship that is the means for seed dispersal for the one group and nutrition for the other; in fact, humans and many animals have become dependent on fruits as a source of food. Consequently, fruits account for a substantial fraction of the world's agricultural output, and some (such as the apple and the pomegranate) have acquired extensive cultural and symbolic meanings. In common language usage, "fruit" normally means the seed-associated fleshy structures (or produce) of plants that typically are sweet or sour and edible in the raw state, such as apples, bananas, grapes, lemons, oranges, and strawberries. In botanical usage, the term "fruit" a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seed Cones
A conifer cone (in formal botanical usage: strobilus, plural strobili) is a seed-bearing organ on gymnosperm plants. It is usually woody, ovoid to globular, including scales and bracts arranged around a central axis, especially in conifers and cycads. The cone of Pinophyta (conifer clade) contains the reproductive structures. The woody cone is the female cone, which produces seeds. The male cone, which produces pollen, is usually herbaceous and much less conspicuous even at full maturity. The name "cone" derives from Greek ''konos'' (pine cone), which also gave name to the geometric cone. The individual plates of a cone are known as ''scales''. The ''umbo'' of a conifer cone refers to the first year's growth of a seed scale on the cone, showing up as a protuberance at the end of the two-year-old scale. The male cone (microstrobilus or pollen cone) is structurally similar across all conifers, differing only in small ways (mostly in scale arrangement) from species to species. E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
