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Dictyosphaerium Ehrenbergianum
''Dictyosphaerium'' is a genus of green algae, in the family Chlorellaceae. It occurs in freshwater habitats around the world and is planktonic. The name comes from the Greek roots ''diktyon'', meaning "net", and ''sphaira'', meaning "ball", referring to its morphology. Description ''Dictyosphaerium'' consists of irregular colonies of 4 to 64 cells in a common mucilaginous envelope 10–100 μm wide. Cells are roughly spherical to ellipsoidal, 1-10 μm in diameter, with one nucleus and a single pyrenoid-containing chloroplast. Cells are attached to the end of thin stalks; the stalks emerge from the center of the colony and continuously branch out. These stalks are formed from the remnants of the mother cell wall. ''Dictyosphaerium'' cells reproduce asexually by autospores. Two or four autospores are produced per sporangium; after release, the mother cell wall gelatinizes and develops into a thin strand, which are connected to the newly released cells. Taxonomy ''Dictyosphaerium ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cell Nucleus
The cell nucleus (; : nuclei) is a membrane-bound organelle found in eukaryote, eukaryotic cell (biology), cells. Eukaryotic cells usually have a single nucleus, but a few cell types, such as mammalian red blood cells, have #Anucleated_cells, no nuclei, and a few others including osteoclasts have Multinucleate, many. The main structures making up the nucleus are the nuclear envelope, a double membrane that encloses the entire organelle and isolates its contents from the cellular cytoplasm; and the nuclear matrix, a network within the nucleus that adds mechanical support. The cell nucleus contains nearly all of the cell's genome. Nuclear DNA is often organized into multiple chromosomes – long strands of DNA dotted with various proteins, such as histones, that protect and organize the DNA. The genes within these chromosomes are Nuclear organization, structured in such a way to promote cell function. The nucleus maintains the integrity of genes and controls the activities of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mychonastes
''Mychonastes'' is a genus of green algae, specifically of the Chlorophyceae. It is the sole genus of the family Mychonastaceae. Species of ''Mychonastes'' are found in plankton of freshwater or brackish waters, or found in soil. It is a very common genus, and is often dominant. Description ''Mychonastes'' consists of solitary cells of groups of a few cells (rarely more than four). Cells are spherical or slightly ovate, uninucleate (with one nucleus) and a single parietal chloroplast without any pyrenoids. The cell wall is covered in an irregular network of ridges, only visible in (scanning electron microscopy). Cells are sometimes connected together by irregular, mucilaginous strands. These mucilaginous strands are formed from the mother cell wall after autospore release. ''Mychonastes'' reproduces asexually via autospores. Usually 2 or 4 (sometimes up to 64) are produced per cell. They are released through a tear in the cell wall. Species are differentiated from each other by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyphyletic
A polyphyletic group is an assemblage that includes organisms with mixed evolutionary origin but does not include their most recent common ancestor. The term is often applied to groups that share similar features known as Homoplasy, homoplasies, which are explained as a result of convergent evolution. The arrangement of the members of a polyphyletic group is called a polyphyly .. [Source for pronunciation.] It is contrasted with monophyly and paraphyly. For example, the biological characteristic of warm-bloodedness evolved separately in the ancestors of mammals and the ancestors of birds; "warm-blooded animals" is therefore a polyphyletic grouping. Other examples of polyphyletic groups are algae, C4 photosynthesis, C4 photosynthetic plants, and Xenarthra#Evolutionary relationships, edentates. Many taxonomists aim to avoid homoplasies in grouping taxa together, with a goal to identify and eliminate groups that are found to be polyphyletic. This is often the stimulus for major re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chlorella
''Chlorella'' is a genus of about thirteen species of single- celled or colonial green algae of the division Chlorophyta. The cells are spherical in shape, about 2 to 10 μm in diameter, and are without flagella. Their chloroplasts contain the green photosynthetic pigments chlorophyll-a and -b. In ideal conditions cells of ''Chlorella'' multiply rapidly, requiring only carbon dioxide, water, sunlight, and a small amount of minerals to reproduce. The name ''Chlorella'' is taken from the Greek χλώρος, ''chlōros/ khlōros'', meaning green, and the Latin diminutive suffix -''ella'', meaning small. German biochemist and cell physiologist Otto Heinrich Warburg, awarded with the Nobel Prize in Physiology or Medicine in 1931 for his research on cell respiration, also studied photosynthesis in ''Chlorella''. In 1961, Melvin Calvin of the University of California received the Nobel Prize in Chemistry for his research on the pathways of carbon dioxide assimilation in plan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molecular Phylogenetic
Molecular phylogenetics () is the branch of phylogeny that analyzes genetic, hereditary molecular differences, predominantly in DNA sequences, to gain information on an organism's evolutionary relationships. From these analyses, it is possible to determine the processes by which diversity among species has been achieved. The result of a molecular phylogenetic analysis is expressed in a phylogenetic tree. Molecular phylogenetics is one aspect of molecular systematics, a broader term that also includes the use of molecular data in taxonomy and biogeography. Molecular phylogenetics and molecular evolution correlate. Molecular evolution is the process of selective changes (mutations) at a molecular level (genes, proteins, etc.) throughout various branches in the tree of life (evolution). Molecular phylogenetics makes inferences of the evolutionary relationships that arise due to molecular evolution and results in the construction of a phylogenetic tree. History The theoretical fra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Botryococcaceae
Botryococcaceae is a family of green algae in the class Trebouxiophyceae. Traditionally, Botryococcaceae has been defined on morphological grounds. Members of this family consist of irregular colonies of cells found free-floating or attached to a substrate. Cells are united by mucilaginous stalks that are formed by the gelatinization of the old parent cell walls. Cells may be spherical, ellipsoidal, or ovoid with a chloroplast with or without a pyrenoid. Reproduction occurs exclusively asexually by the formation of autospores. However, molecular phylogenetic studies have found that some genera placed in Botryococcaceae based on morphology alone are unrelated to ''Botryococcus''; the genus '' Dictyosphaerium'' is now placed in the family Chlorellaceae Chlorellaceae are a family of green algae in the order Chlorellales. About 250 species are currently accepted in the family. Members of the family are distributed worldwide and are common in a variety of freshwater, terrestrial a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Autospore
Autospores are a type of spores that are produced by algae to enable asexual reproduction and spread. They are non-motile and non-Flagellated cell, flagellated Aplanospore, aplanospores that are generated within a parent cell and have the same shape as the parent cell before their release. Autospores are also known as resting spores. Algae primarily use three different types of spores for asexual reproduction - autospores, Zoospore, zoospores, and aplanospores. Autospores occur in several groups of algae, including ''Eustigmatophyceae'', ''Dinoflagellate, Dinoflagellates'', and green algae. One example of a colonial alga that produces autospores is Dichotomococcus. This alga generates two autospores per reproducing cell, and the autospores escape through a slit in the cell wall and remain attached to the mother cell. Some study on autospores and algae in general include looking into its use for biofuel, animal feed, food supplements, nutraceuticals, and pharmaceuticals. Autospore ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
