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Mitochondrial Decay
A mitochondrion () is an organelle found in the cells of most eukaryotes, such as animals, plants and fungi. Mitochondria have a double 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'', meaning a thread-like granule, was coined by Carl Benda in 1898. The mitochondrion is popularly nicknamed the "powerhouse of the cell", a phrase popularized by Philip Siekevitz in a 1957 ''Scientific American'' article of the same name. Some cells in some multicellular organisms lack mitochondria (for example, mature mammalian red blood cells). The multicellular animal ''Henneguya salminicola'' is known to have retained mitochondrion-related organelles despite a complete loss of their mitochondrial genome. A large number of unicellular organisms, such as microsporidia, par ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Cell (biology)
The cell is the basic structural and functional unit of all life, forms of life. Every cell consists of cytoplasm enclosed within a Cell membrane, membrane; many cells contain organelles, each with a specific function. The term comes from the Latin word meaning 'small room'. Most cells are only visible under a light microscope, microscope. Cells Abiogenesis, emerged on Earth about 4 billion years ago. All cells are capable of Self-replication, replication, protein synthesis, and cell motility, motility. Cells are broadly categorized into two types: eukaryotic cells, which possess a Cell nucleus, nucleus, and prokaryotic, prokaryotic cells, which lack a nucleus but have a nucleoid region. Prokaryotes are single-celled organisms such as bacteria, whereas eukaryotes can be either single-celled, such as amoebae, or multicellular organism, multicellular, such as some algae, plants, animals, and fungi. Eukaryotic cells contain organelles including Mitochondrion, mitochondria, which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Philip Siekevitz
Philip Siekevitz (February 25, 1918 – December 5, 2009) was an American cell biologist who spent most of his career at Rockefeller University. He was involved in early studies of protein synthesis and trafficking, established purification techniques to facilitate study of the cell nucleus, worked with Nobel Prize in Physiology or Medicine winner George Palade on cell membrane dynamics, and published extensively on the subject of postsynaptic density. Early life and education Siekevitz was born on February 25, 1918, in Philadelphia to a working-class immigrant family. He spent two years after high school working to save money for his college education, and then began at the Philadelphia College of Pharmacy and Science. He was drafted into the United States Army during his senior year, but deferred his service until after his graduation in 1942. He then served in the army for almost four years, first in a chemical warfare response unit and later as a laboratory technician. Si ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Streblomastix
A symbiotic eukaryote that lives in the hindgut of termites, ''Streblomastix'' is a protist associated with a community of ectosymbiotic bacteria. Motility ''Streblomastix'' moves by beating its anterior flagella. Morphology These protists A protist ( ) or protoctist is any Eukaryote, eukaryotic organism that is not an animal, Embryophyte, land plant, or fungus. Protists do not form a Clade, natural group, or clade, but are a Paraphyly, paraphyletic grouping of all descendants o ... measure around 100 micrometers in length. They completely lack mitochondria. References *http://www.microscopy-uk.org.uk/mag/indexmag.html?http://www.microscopy-uk.org.uk/mag/artmar03/rhtermite.html *http://www.ucmp.berkeley.edu/protista/basalprotists.html {{Taxonbar, from=Q7622748 Metamonads Metamonad genera Anaerobes Microorganisms Symbiosis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Monocercomonoides
''Monocercomonoides'' is a genus of flagellate Excavata belonging to the order Oxymonadida. It was established by Bernard V. Travis and was first described as those with "polymastiginid flagellates having three anterior Flagellum, flagella and a trailing one originating at a single basal granule located in front of the anteriorly positioned cell nucleus, nucleus, and a more or less well-defined axostyle". It is the first eukaryotic genus to be found to completely lack Mitochondrion, mitochondria, and all hallmark proteins responsible for mitochondrial function. The genus also lacks any other Mitochondrion#Origin and evolution, mitochondria related organelles (MROs) such as hydrogenosomes or mitosomes. Data suggests that the absence of mitochondria is not an ancestral feature, but rather due to secondary loss. ''Monocercomonoides ''sp. was found to obtain energy through an enzymatic action of nutrients absorbed from the environment. The genus has replaced the Iron–sulfur protein ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Oxymonad
The Oxymonads (or Oxymonadida) are a group of flagellated protists found exclusively in the intestines of animals, mostly termites and other Xylophagy, wood-eating insects. Along with the similar parabasalid flagellates, they harbor the Symbiosis, symbiotic bacterium, bacteria that are responsible for breaking down cellulose. There is no evidence for presence of Mitochondrion, mitochondria (not even anaerobic mitochondrion-like organelles like hydrogenosomes or mitosomes) in oxymonads and three species have been shown to completely lack any molecular markers of mitochondria. It includes e.g. ''Dinenympha'', ''Pyrsonympha'', ''Oxymonas'', ''Streblomastix'', ''Monocercomonoides'', and ''Blattamonas''. Characteristics Most Oxymonads are around 50 μm in size and have a single cell nucleus, nucleus, associated with four Flagellum, flagella. Their Basal body, basal bodies give rise to several long sheets of microtubules, which form an organelle called an axostyle, but different in st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Mitosome
A mitosome (also called a ''crypton'' in early literature) is a mitochondrion-related organelle (MRO) found in a variety of parasitic unicellular eukaryotes, such as members of the supergroup Excavata. The mitosome was first discovered in 1999 in ''Entamoeba histolytica,'' an intestinal parasite of humans, and mitosomes have also been identified in several species of Microsporidia and in '' Giardia intestinalis''. The mitosome has been detected only in anaerobic or microaerophilic eukaryotes which do not have fully developed mitochondria, and hence do not have the capability of gaining energy from mitochondrial oxidative phosphorylation. The functions of mitosomes, while varied, have not yet been well characterized, but they may be associated with sulfate metabolism and biosynthesis of phospholipids and Fe–S clusters. Mitosomes, like other MROs, likely evolved from mitochondria, based on similarities in structure, function, and biochemical signaling pathways, and may have conve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
