Pinophyta in the context of "Gymnosperms"

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Pinophyta in the context of Gymnosperm

The gymnosperms (/ˈɪmnəˌspɜːrmz, -n-/ nə-spurmz, -⁠noh-; from Ancient Greek γυμνός (gumnós), meaning "naked", and σπέρμα (spérma), meaning "seed", and thus, "naked seed") are a group of woody, perennial seed-producing plants, typically lacking the protective outer covering which surrounds the seeds in flowering plants, that include conifers, cycads, Ginkgo, and gnetophytes, forming the clade Gymnospermae. The name is based on the unenclosed condition of their seeds (called ovules in their unfertilized state). The non-encased condition of their seeds contrasts with the seeds and ovules of flowering plants (angiosperms), which are enclosed within an ovary. Gymnosperm seeds develop either on the surface of scales or leaves, which are often modified to form cones, or on their own as in yew, Torreya, and Ginkgo.

The life cycle of a gymnosperm involves alternation of generations, with a dominant diploid sporophyte phase, and a reduced haploid gametophyte phase, which is dependent on the sporophytic phase. The term "gymnosperm" is often used in paleobotany to refer to (the paraphyletic group of) all non-angiosperm seed plants. In that case, to specify the modern monophyletic group of gymnosperms, the term Acrogymnospermae is sometimes used.

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Pinophyta in the context of Charophyta

Charophyta (UK: /kəˈrɒfɪtə, ˌkærəˈftə/) is a paraphyletic group of freshwater green algae, called charophytes (/ˈkærəˌfts/), sometimes treated as a division, yet also as a superdivision. The terrestrial plants, the Embryophyta emerged deep within Charophyta, possibly from terrestrial unicellular charophytes, with the class Zygnematophyceae as a sister group.

With the Embryophyta now cladistically placed in the Charophyta, it is a synonym of Streptophyta. The sister group of the charophytes are the Chlorophyta. In some charophyte groups, such as the Zygnematophyceae or conjugating green algae, flagella are absent and sexual reproduction does not involve free-swimming flagellate sperm. Flagellate sperm, however, are found in stoneworts (Charales) and Coleochaetales, orders of parenchymatous charophytes that are the closest relatives of the land plants, where flagellate sperm are also present in all except the conifers and flowering plants. Fossil stoneworts of early Devonian age that are similar to those of the present day have been described from the Rhynie chert of Scotland. Somewhat different charophytes have also been collected from the Late Devonian (Famennian) Waterloo Farm lagerstätte of South Africa. These include two species each of Octochara and Hexachara, which are the oldest fossils of Charophyte axes bearing in situ oogonia.

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Pinophyta in the context of Taiga

Taiga or tayga (/ˈtɡə/ TY-gə; Russian: тайга́, IPA: [tɐjˈɡa]), also known as boreal forest or snow forest, is a biome characterized by coniferous forests consisting mostly of pines, spruces, and larches. The taiga, or boreal forest, is the world's largest land biome. In North America, it covers most of inland Canada, Alaska, and parts of the northern contiguous United States. In Eurasia, it covers most of Sweden, Finland, much of Russia from Karelia in the west to the Pacific Ocean (including much of Siberia), much of Norway and Estonia, some of the Scottish Highlands, some lowland/coastal areas of Iceland, and areas of northern Kazakhstan, northern Mongolia, and northern Japan (on the island of Hokkaido).

The principal tree species, depending on the length of the growing season and summer temperatures, vary across the world. The taiga of North America is mostly spruce; Scandinavian and Finnish taiga consists of a mix of spruce, pines and birch; Russian taiga has spruces, pines and larches depending on the region; and the Eastern Siberian taiga is a vast larch forest.

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Pinophyta in the context of Cryptomeria

Cryptomeria (literally "hidden parts") is a monotypic genus of conifer in the cypress family Cupressaceae. It includes only one species, Cryptomeria japonica (syn. Cupressus japonica L.f.). It is considered to be endemic to Japan, where it is known as Sugi (). The tree is also called Japanese cedar or Japanese redwood in English. It has been extensively introduced, and cultivated for wood production on the Azores and elsewhere.

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Pinophyta in the context of Conifer cone

A conifer cone, or in formal botanical usage a strobilus, pl.: strobili, is a seed-bearing organ on gymnosperm plants, especially in conifers and cycads. They are usually woody and variously conic, cylindrical, ovoid, to globular, and have scales and bracts arranged around a central axis, but can be fleshy and berry-like. The cones of Pinophyta (conifer clade) contain the reproductive structures. The woody cone is the female cone, which produces seeds. The male cone, which produces pollen, is usually ephemeral 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. In conifers where the cone develops over more than one year (such as pines), 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, is called an umbo, while the second year's growth is called the apophysis.

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. Extending out from a central axis are microsporophylls (modified leaves). Under each microsporophyll is one or several microsporangia (pollen sacs).

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Pinophyta in the context of Cupressus

Cupressus (common name cypress) is one of several genera of evergreen conifers within the family Cupressaceae; for the others, see cypress. It is considered a polyphyletic group. Based on genetic and morphological analysis, the genus Cupressus is found in the subfamily Cupressoideae. The common name "cypress" comes via the Old French cipres from the Latin cyparissus, which is the latinisation of the Greek κυπάρισσος (kypárissos). The name derives from Cyparissus, a mythological figure who was turned into a tree after killing a stag.

As currently treated, these cypresses are native plants in scattered localities in mainly warm temperate climate regions in the Northern Hemisphere, including northwest Africa, the Middle East, the Himalayas, southern China and northern Vietnam. As with other conifers, extensive cultivation has led to a wide variety of forms, sizes and colours, that are grown in parks and gardens worldwide.

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Pinophyta in the context of Metasequoia glyptostroboides

Metasequoia glyptostroboides, the dawn redwood, is a fast-growing, endangered deciduous conifer. It is the sole living species of the genus Metasequoia, one of three genera in the subfamily Sequoioideae of the family Cupressaceae. It now survives in the wild only in wet lower slopes and montane river and stream valleys in the border region of Hubei and Hunan provinces and Chongqing municipality in south-central China, notably in Lichuan county in Hubei. Although the shortest of the redwoods, it can grow to 167 ft (51 m) in height.

In 1941, the genus Metasequoia was reported by paleobotanist Shigeru Miki [jp] as a widely distributed extinct genus based on fossils, before attracting considerable attention a few years later when small populations were found alive in central China. It is a well-known example of a living fossil species. Modern dawn redwood appears identical to its late Cretaceous ancestors. The tree faces considerable risks of extinction in its wild range due to deforestation; however, it has been planted extensively in arboreta worldwide, where it has proved a popular and fast-growing ornamental plant. If the species had not been discovered when it was, it might have become extinct before being investigated.

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