Plants

Plants are mainly multicellular, predominantly photosynthetic eukaryotes of the kingdom Plantae. Historically, plants were treated as one of two kingdoms including all living things that were not animals, and all algae and fungi were treated as plants. However, all current definitions of Plantae exclude the fungi and some algae, as well as the prokaryotes (the archaea and bacteria). By one definition, plants form the clade Viridiplantae (Latin name for "green plants"), a group that includes the flowering plants, conifers and other gymnosperms, ferns and their allies, hornworts, liverworts, mosses and the green algae, but excludes the red and brown algae.

Green plants obtain most of their energy from sunlight via photosynthesis by primary chloroplasts that are derived from endosymbiosis with cyanobacteria. Their chloroplasts contain chlorophylls a and b, which gives them their green color. Some plants are parasitic or mycotrophic and have lost the ability to produce normal amounts of chlorophyll or to photosynthesize. Plants are characterized by sexual reproduction and alternation of generations, although asexual reproduction is also common.

There are about 320 thousand species of plants, of which the great majority, some 260–290 thousand, are seed plants (see the table below). Green plants provide a substantial proportion of the world's molecular oxygen and are the basis of most of Earth's ecosystems, especially on land. Plants that produce grain, fruit and vegetables form humankind's basic foods, and have been domesticated for millennia. Plants have many cultural and other uses, as ornaments, building materials, writing material and, in great variety, they have been the source of medicines and psychoactive drugs. The scientific study of plants is known as botany, a branch of biology.

Definition
All living things were traditionally placed into one of two groups, plants and animals. This classification may date from Aristotle (384 BC – 322 BC), who made the distincton between plants, which generally do not move, and animals, which often are mobile to catch their food. Much later, when Linnaeus (1707–1778) created the basis of the modern system of scientific classification, these two groups became the kingdoms Vegetabilia (later Metaphyta or Plantae) and Animalia (also called Metazoa). Since then, it has become clear that the plant kingdom as originally defined included several unrelated groups, and the fungi and several groups of algae were removed to new kingdoms. However, these organisms are still often considered plants, particularly in popular contexts.

The term "plant" generally implies the possession of the following traits: multicellularity, possession of cell walls containing cellulose, and the ability to carry out photosynthesis with primary chloroplasts.



The Major Groups


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Hainan gibbon

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Species  -  Latest posts  /  Genres  -  Latest posts  /  Animals  -  Latest posts  /  Mammals Hainan gibbon The Hainan black-crested gibbon or Hainan gibbon (Nomascus hainanus), is a species of gibbon found only on Hainan Island, China. It was formerly considered a subspecies of the eastern black crested gibbon (Nomascus nasutus) from Hòa Bình and Cao Bằng provinces of Vietnam and Jingxi County in Guangxi Zhuang Autonomous Region, China. Molecular data, together with morphology and call differences, suggest it is a separate species. Its habitat consists of broad-leaved forests and semi-deciduous monsoon forests. It feeds on ripe, sugar-rich fruit, such as figs (Ficus spp.) and, at times, leaves, and insects. Current status Hainan black-crested gibbons are under grave threat of extinction. They are currently identified as critically endangered on the International Union for Conservation of Nature’s Red List. Historically, they w...
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Space Shuttle Challenger explodes shortly after take-off

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Space Shuttle Challenger disintegrates 73 seconds after its 1986 launch resulting in the death of all seven crew members. Space Shuttle Challenger explodes shortly after take-off. On January 28, 1986, the Space Shuttle Challenger and her seven-member crew were lost when a ruptured O-ring in the right Solid Rocket Booster caused an explosion soon after launch. This photograph, taken a few seconds after the accident, shows the Space Shuttle Main Engines and Solid Rocket Booster exhaust plumes entwined around a ball of gas from the External Tank. Because shuttle launches had become almost routine after twenty-four successful missions, those watching the shuttle launch in person and on television found the sight of the explosion especially shocking and difficult to believe until NASA confirmed the accident. Image # : 86-HC-220 Title: Exhaust Trail of STS-51-L
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Wild life

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Species  :  Wild life - Later posts Wildlife Wildlife traditionally refers to undomesticated animal species, but has come to include all organisms that grow or live wild in an area without being introduced by humans. Wildlife can be found in all ecosystems. Deserts, forests, rain forests, plains, grasslands and other areas including the most developed urban areas, all have distinct forms of wildlife. While the term in popular culture usually refers to animals that are untouched by human factors, most scientists agree that much wildlife is affected by human activities. Humans have historically tended to separate civilization from wildlife in a number of ways including the legal, social, and moral sense. Some animals, however, have adapted to suburban environments. This includes such animals as domesticated cats, dogs, mice, and gerbils. Some religions declare certain animals to be sacred, and in modern times concern for the natural environment has provoked activists to protest...
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