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Ocelloid
An ocelloid is a subcellular structure found in the family Warnowiaceae (warnowiids), which are members of a group of unicellular organisms known as dinoflagellates. The ocelloid is analogous in structure and function to the eyes of multicellular organisms, which focus, process and detect light. The ocelloid is much more complex than the eyespot, a light-sensitive structure also found in unicellular organisms, and is in fact one of the most complex known subcellular structures. It has been described as a striking example of convergent evolution. History The ocelloid was originally described in 1884. Early descriptions were met with skepticism and hypothesized to represent the eye of a multicellular organism coincidentally engulfed by a single-celled organism. The possibility that it had an evolutionary relationship to plastids had been considered at least since the 1970s, although until the 2010s direct evidence was scarce. Structure Ocelloids contain subcomponents analogou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Warnowiaceae
The Warnowiaceae are a family of athecate dinoflagellates (a diverse group of unicellular eukaryotes). Members of the family are known as warnowiids. The family is best known for a light-sensitive subcellular structure known as the ocelloid, a highly complex arrangement of organelles with a structure directly analogous to the eyes of multicellular organisms. The ocelloid has been shown to be composed of multiple types of endosymbionts, namely mitochondria and at least one type of plastid. Habitat and life cycle Warnowiids are found in marine plankton but are very rare in most plankton samples. Little is known about their life histories because they cannot be cultured in the laboratory, and samples obtained from the natural environment do not survive well under laboratory conditions. Studies of wild samples have found evidence of distinctive structures called trichocysts in warnowiid cell vacuoles, suggesting that their prey might be other dinoflagellates. Despite the complexity o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organelle
In cell biology, an organelle is a specialized subunit, usually within a cell, that has a specific function. The name ''organelle'' comes from the idea that these structures are parts of cells, as organs are to the body, hence ''organelle,'' the suffix ''-elle'' being a diminutive. Organelles are either separately enclosed within their own lipid bilayers (also called membrane-bound organelles) or are spatially distinct functional units without a surrounding lipid bilayer (non-membrane bound organelles). Although most organelles are functional units within cells, some function units that extend outside of cells are often termed organelles, such as cilia, the flagellum and archaellum, and the trichocyst. Organelles are identified by microscopy, and can also be purified by cell fractionation. There are many types of organelles, particularly in eukaryotic cells. They include structures that make up the endomembrane system (such as the nuclear envelope, endoplasmic reticulum, and G ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ocellus
A simple eye (sometimes called a pigment pit) refers to a form of eye or an optical arrangement composed of a single lens and without an elaborate retina such as occurs in most vertebrates. In this sense "simple eye" is distinct from a multi-lensed "compound eye", and is not necessarily at all simple in the usual sense of the word. The structure of an animal's eye is determined by the environment in which it lives, and the behavioural tasks it must fulfill to survive. Arthropods differ widely in the habitats in which they live, as well as their visual requirements for finding food or conspecifics, and avoiding predators. Consequently, an enormous variety of eye types are found in arthropods. They possess a wide variety of novel solutions to overcome visual problems or limitations. Use of the term ''simple eye'' is flexible, and must be interpreted in proper context; for example, the eyes of humans and of other large animals such as most cephalopods, are ''camera eyes'' and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mitochondria
A mitochondrion (; ) is an organelle found in the Cell (biology), cells of most Eukaryotes, such as animals, plants and Fungus, fungi. Mitochondria have a double lipid bilayer, membrane structure and use aerobic respiration to generate adenosine triphosphate (ATP), which is used throughout the cell as a source of chemical energy. They were discovered by Albert von Kölliker in 1857 in the voluntary muscles of insects. The term ''mitochondrion'' was coined by Carl Benda in 1898. The mitochondrion is popularly nicknamed the "powerhouse of the cell", a phrase coined by Philip Siekevitz in a 1957 article of the same name. Some cells in some multicellular organisms lack mitochondria (for example, mature mammalian red blood cells). A large number of unicellular organisms, such as microsporidia, parabasalids and diplomonads, have reduced or transformed their mitochondria into mitosome, other structures. One eukaryote, ''Monocercomonoides'', is known to have completely lost its mitocho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plos One Hayakawa Erythropsidinium Ocelloid EM FigS1
PLOS (for Public Library of Science; PLoS until 2012 ) is a nonprofit publisher of open-access journals in science, technology, and medicine and other scientific literature, under an open-content license. It was founded in 2000 and launched its first journal, ''PLOS Biology'', in October 2003. As of 2022, PLOS publishes 12 academic journals, including 7 journals indexed within the Science Citation Index Expanded, and consequently 7 journals ranked with an impact factor. PLOS journals are included in the Directory of Open Access Journals (DOAJ). PLOS is also a member of the Open Access Scholarly Publishers Association (OASPA), a participating publisher and supporter of the Initiative for Open Citations, and a member of the Committee on Publication Ethics (COPE). History The Public Library of Science began in 2000 with an online petition initiative by Nobel Prize winner Harold Varmus, formerly director of the National Institutes of Health and at that time director ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Popular Science
''Popular Science'' (also known as ''PopSci'') is an American digital magazine carrying popular science content, which refers to articles for the general reader on science and technology subjects. ''Popular Science'' has won over 58 awards, including the American Society of Magazine Editors awards for its journalistic excellence in 2003 (for General Excellence), 2004 (for Best Magazine Section), and 2019 (for Single-Topic Issue). With roots beginning in 1872, ''Popular Science'' has been translated into over 30 languages and is distributed to at least 45 countries. Early history ''The Popular Science Monthly'', as the publication was originally called, was founded in May 1872 by Edward L. Youmans to disseminate scientific knowledge to the educated layman. Youmans had previously worked as an editor for the weekly ''Appleton's Journal'' and persuaded them to publish his new journal. Early issues were mostly reprints of English periodicals. The journal became an outlet for writings ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peridinin
Peridinin is a light-harvesting apocarotenoid, a pigment associated with chlorophyll and found in the peridinin-chlorophyll-protein (PCP) light-harvesting complex in dinoflagellates, best studied in ''Amphidinium carterae''. Biological significance Peridinin is an apocarotenoid pigment that some organisms use in photosynthesis. Many photosynthetic dinoflagellates use peridinin, which absorbs blue-green light in the 470-550nm range, outside the range accessible to chlorophyll molecules. The peridinin-chlorophyll-protein complex is a specialized molecular complex consisting of a boat-shaped protein molecule with a large central cavity that contains peridinin, chlorophyll, and lipid molecules, usually in a 4:1 ratio of peridinin to chlorophyll. Spectral characteristics * Absorption maximum: 483 nm * Emission maximum: 676 nm * Extinction coefficient (ε): 1.96 x 106 M−1cm−1 * A483/A280 ≥ 4.6 Applications Peridinin chlorophyll (PerCP) is commonly used in immunoassa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endosymbiotic
An ''endosymbiont'' or ''endobiont'' is any organism that lives within the body or cells of another organism most often, though not always, in a mutualistic relationship. (The term endosymbiosis is from the Greek: ἔνδον ''endon'' "within", σύν ''syn'' "together" and βίωσις ''biosis'' "living".) Examples are nitrogen-fixing bacteria (called rhizobia), which live in the root nodules of legumes, single-cell algae inside reef-building corals and bacterial endosymbionts that provide essential nutrients to insects. There are two types of symbiont transmissions. In horizontal transmission, each new generation acquires free living symbionts from the environment. An example is the nitrogen-fixing bacteria in certain plant roots. Vertical transmission takes place when the symbiont is transferred directly from parent to offspring. It is also possible for both to be involved in a mixed-mode transmission, where symbionts are transferred vertically for some generation bef ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cell Membrane
The cell membrane (also known as the plasma membrane (PM) or cytoplasmic membrane, and historically referred to as the plasmalemma) is a biological membrane that separates and protects the interior of all cells from the outside environment (the extracellular space). The cell membrane consists of a lipid bilayer, made up of two layers of phospholipids with cholesterols (a lipid component) interspersed between them, maintaining appropriate membrane fluidity at various temperatures. The membrane also contains membrane proteins, including integral proteins that span the membrane and serve as membrane transporters, and peripheral proteins that loosely attach to the outer (peripheral) side of the cell membrane, acting as enzymes to facilitate interaction with the cell's environment. Glycolipids embedded in the outer lipid layer serve a similar purpose. The cell membrane controls the movement of substances in and out of cells and organelles, being selectively permeable to ions a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electron Microscopy
An electron microscope is a microscope that uses a beam of accelerated electrons as a source of illumination. As the wavelength of an electron can be up to 100,000 times shorter than that of visible light photons, electron microscopes have a higher resolving power than light microscopes and can reveal the structure of smaller objects. A scanning transmission electron microscope has achieved better than 50 pm resolution in annular dark-field imaging mode and magnifications of up to about 10,000,000× whereas most light microscopes are limited by diffraction to about 200 nm resolution and useful magnifications below 2000×. Electron microscopes use shaped magnetic fields to form electron optical lens systems that are analogous to the glass lenses of an optical light microscope. Electron microscopes are used to investigate the ultrastructure of a wide range of biological and inorganic specimens including microorganisms, cells, large molecules, biopsy samples, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genomics
Genomics is an interdisciplinary field of biology focusing on the structure, function, evolution, mapping, and editing of genomes. A genome is an organism's complete set of DNA, including all of its genes as well as its hierarchical, three-dimensional structural configuration. In contrast to genetics, which refers to the study of ''individual'' genes and their roles in inheritance, genomics aims at the collective characterization and quantification of ''all'' of an organism's genes, their interrelations and influence on the organism. Genes may direct the production of proteins with the assistance of enzymes and messenger molecules. In turn, proteins make up body structures such as organs and tissues as well as control chemical reactions and carry signals between cells. Genomics also involves the sequencing and analysis of genomes through uses of high throughput DNA sequencing and bioinformatics to assemble and analyze the function and structure of entire genomes. Advances in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Single Cell Genome Sequencing
Whole genome sequencing (WGS), also known as full genome sequencing, complete genome sequencing, or entire genome sequencing, is the process of determining the entirety, or nearly the entirety, of the DNA sequence of an organism's genome at a single time. This entails sequencing all of an organism's chromosomal DNA as well as DNA contained in the mitochondria and, for plants, in the chloroplast. Whole genome sequencing has largely been used as a research tool, but was being introduced to clinics in 2014. In the future of personalized medicine, whole genome sequence data may be an important tool to guide therapeutic intervention. The tool of gene sequencing at SNP level is also used to pinpoint functional variants from association studies and improve the knowledge available to researchers interested in evolutionary biology, and hence may lay the foundation for predicting disease susceptibility and drug response. Whole genome sequencing should not be confused with DNA profilin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
