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Vorticella Campanula
The protozoon ''Vorticella campanula'' is found in freshwater ponds, lakes, rivers, and streams with aquatic vegetation. It has a global distribution. ''Vorticella campanula'' is solitary and not colonial but usually social, several of them being found together. ''Vorticella campanula'' is a sedentary (fixed) form. It is commonly attached by a long highly contractile stalk to some submerged objects like weeds, animals, or stones. ''Vorticella campanula'' is often found in large groups. All the individuals in the group, however, remain free and independent of each other. Most ''Vorticella'' are found in abundance in stagnant water rich in decaying organic matter and feed largely on bacteria Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were among ..., but ''Vorticella campanula'' live only i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protozoon
Protozoa (singular: protozoan or protozoon; alternative plural: protozoans) are a group of single-celled eukaryotes, either free-living or parasitic, that feed on organic matter such as other microorganisms or organic tissues and debris. Historically, protozoans were regarded as "one-celled animals", because they often possess animal-like behaviours, such as motility and predation, and lack a cell wall, as found in plants and many algae. When first introduced by Georg Goldfuss (originally spelled Goldfuß) in 1818, the taxon Protozoa was erected as a class within the Animalia, with the word 'protozoa' meaning "first animals". In later classification schemes it was elevated to a variety of higher ranks, including phylum, subkingdom and kingdom, and sometimes included within Protoctista or Protista. The approach of classifying Protozoa within the context of Animalia was widespread in the 19th and early 20th century, but not universal. By the 1970s, it became usual to require th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Social
Social organisms, including human(s), live collectively in interacting populations. This interaction is considered social whether they are aware of it or not, and whether the exchange is voluntary or not. Etymology The word "social" derives from the Latin word ''socii'' ("allies"). It is particularly derived from the Italian ''Socii'' states, historical allies of the Roman Republic (although they rebelled against Rome in the Social War of 91–87 BC). Social theorists In the view of Karl MarxMorrison, Ken. ''Marx, Durkheim, Weber. Formations of modern social thought'', human beings are intrinsically, necessarily and by definition social beings who, beyond being "gregarious creatures", cannot survive and meet their needs other than through social co-operation and association. Their social characteristics are therefore to a large extent an objectively given fact, stamped on them from birth and affirmed by socialization processes; and, according to Marx, in producing and reproducin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sedentary
Sedentary lifestyle is a lifestyle type, in which one is physically inactive and does little or no physical movement and or exercise. A person living a sedentary lifestyle is often sitting or lying down while engaged in an activity like socializing, watching TV, playing video games, reading or using a mobile phone or computer for much of the day. A sedentary lifestyle contributes to poor health quality, diseases as well as many preventable causes of death. Sitting time is a common measure of a sedentary lifestyle. A global review representing 47% of the global adult population found that the average person sits down for 4.7 to 6.5 hours a day with the average going up every year. The CDC found that 25.3% of all American adults are physically inactive. Screen time is a term for the amount of time a person spends looking at a screen such as a television, computer monitor, or mobile device. Excessive screen time is linked to negative health consequences. Definition Sedentary ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Contractile
Contractility refers to the ability for self-contraction, especially of the muscles or similar active biological tissue *Contractile ring in cytokinesis *Contractile vacuole *Muscle contraction **Myocardial contractility *See contractile cell for an overview of cell types in humans. See also *motility Motility is the ability of an organism to move independently, using metabolic energy. Definitions Motility, the ability of an organism to move independently, using metabolic energy, can be contrasted with sessility, the state of organisms th ... {{SIA Cell movement ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stagnant Water
Water stagnation occurs when water stops flowing. Stagnant water can be a major environmental hazard. Dangers Malaria and dengue are among the main dangers of stagnant water, which can become a breeding ground for the mosquitoes that transmit these diseases. Stagnant water can be dangerous for drinking because it provides a better incubator than running water for many kinds of bacteria and parasites. Stagnant water can be contaminated with human and animal feces, particularly in deserts or other areas of low rainfall. Water stagnation for as little as six days can completely change bacterial community composition and increase cell count. Stagnant water may be classified into the following basic, although overlapping, types: * Water body stagnation (stagnation in swamp, lake, lagoon, river, etc.) * Surface and ground waters stagnation * Trapped water stagnation. The water may be trapped in human artifacts (discarded cans, plant pots, tires, dug-outs, roofs, etc.), as well as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacteria
Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were among the first life forms to appear on Earth, and are present in most of its habitats. Bacteria inhabit soil, water, acidic hot springs, radioactive waste, and the deep biosphere of Earth's crust. Bacteria are vital in many stages of the nutrient cycle by recycling nutrients such as the fixation of nitrogen from the atmosphere. The nutrient cycle includes the decomposition of dead bodies; bacteria are responsible for the putrefaction stage in this process. In the biological communities surrounding hydrothermal vents and cold seeps, extremophile bacteria provide the nutrients needed to sustain life by converting dissolved compounds, such as hydrogen sulphide and methane, to energy. Bacteria also live in symbiotic and parasitic relationsh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oligohymenophorea
The Oligohymenophorea are a large class of ciliates. There is typically a ventral groove containing the mouth and distinct oral cilia, separate from those of the body. These include a paroral membrane to the right of the mouth and membranelles, usually three in number, to its left. The cytopharynx is inconspicuous and never forms the complex cyrtos found in similar classes. Body cilia generally arise from monokinetids, with dikinetids occurring in limited distribution over part of the body. In most groups the body cilia are uniform and often dense, while the oral cilia are inconspicuous and sometimes reduced, but among the peritrichs almost the opposite is the case. Members are widely distributed, and include many free-living (typically fresh-water, but many marine) and symbiotic forms. Most are microphagous, grazing on smaller organisms swept into the mouth by the cilia, but various other feeding habits occur. In one group, the astomes, the mouth and associated structure ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Articles Containing Video Clips
Article often refers to: * Article (grammar), a grammatical element used to indicate definiteness or indefiniteness * Article (publishing), a piece of nonfictional prose that is an independent part of a publication Article may also refer to: Government and law * Article (European Union), articles of treaties of the European Union * Articles of association, the regulations governing a company, used in India, the UK and other countries * Articles of clerkship, the contract accepted to become an articled clerk * Articles of Confederation, the predecessor to the current United States Constitution *Articles of Impeachment, Article of Impeachment, a formal document and charge used for impeachment in the United States * Articles of incorporation, for corporations, U.S. equivalent of articles of association * Articles of organization, for limited liability organizations, a U.S. equivalent of articles of association Other uses * Article, an HTML element, delimited by the tags and * Ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species Described In 1831
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. Other ways of defining species include their karyotype, DNA sequence, morphology, behaviour or ecological niche. In addition, paleontologists use the concept of the chronospecies since fossil reproduction cannot be examined. The most recent rigorous estimate for the total number of species of eukaryotes is between 8 and 8.7 million. However, only about 14% of these had been described by 2011. All species (except viruses) are given a two-part name, a "binomial". The first part of a binomial is the genus to which the species belongs. The second part is called the specific name or the specific epithet (in botanical nomenclature, also sometimes in zoological ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
