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Helical Growth
Helical growth is when cells or organs expand, resulting in helical shaped cells or organs and typically including the breakage of symmetry. This is seen in fungi, algae, and other higher plant cells or organs. Helical growth can occur naturally, such as in tendrils or in twining plants. Asymmetry can be caused by changes in pectin or through mutation and result in left- or right-handed helices. Tendril perversion, during which a tendril curves in opposite directions at each end, is seen in many cases. The helical growth of twining plants is based on the circumnutational movement, or circular growth, of stems. Most twining plans have right-handed helices regardless of the plant's growth hemisphere. Helical growth in single cells, such as the fungi genus ''Phycomyces'' or the algae genus '' Nitella'', is thought to be caused by a helical arrangement of structural biological material in the cell wall. In mutant thale cress, helical growth is seen at the organ level. Analysis s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phycomyces
''Phycomyces'' is a genus of fungus in the Zygomycota phylum. They are known for their strong phototropism response and helical growth of the sporangium. The best studied species is '' Phycomyces blakesleeanus''. Asexual reproduction ''Phycomyces'' can reproduce via extension of mycelia, or by production of spores either asexually or sexually. The asexual cycle includes the formation of spore containing sporangia borne on the top of sporangiophores that may extend 10 to 15 cm above the surface of the fungal colony from which they emerged. The long filamentous sporangiophores respond to divergent environmental signals including light, gravity, wind, chemicals and adjacent objects. The sporangia contain vegetative spores with one to six haploid nuclei. These spores when dispersed can establish new colonies. Sexual reproduction ''Phycomyces'' have two mating types that are indistinguishable morphologically. The sexual cycle is thought to occur by the following steps. Two h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GOLGA4
Golgin subfamily A member 4 is a protein that in humans is encoded by the ''GOLGA4'' gene. The Golgi apparatus, which participates in glycosylation and transport of proteins and lipids in the secretory pathway, consists of a series of stacked cisternae (flattened membrane sacs). Interactions between the Golgi and microtubules are thought to be important for the reorganization of the Golgi after it fragments during mitosis. The golgins are a family of proteins, of which the protein encoded by this gene is a member, that are localized to the Golgi. This protein has been postulated to play a role in Rab6-regulated membrane-tethering events in the Golgi apparatus. Alternative splice variants have been described but their full-length nature has not been determined. Interactions GOLGA4 has been shown to interact with ARL1 ADP-ribosylation factor-like protein 1 is a protein that in humans is encoded by the ''ARL1'' gene. Function The protein encoded by this gene belongs to the ARL ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Missense Mutation
In genetics, a missense mutation is a point mutation in which a single nucleotide change results in a codon that codes for a different amino acid. It is a type of nonsynonymous substitution. Substitution of protein from DNA mutations Missense mutation refers to a change in one amino acid in a protein, arising from a point mutation in a single nucleotide. Missense mutation is a type of nonsynonymous substitution in a DNA sequence. Two other types of nonsynonymous substitution are the nonsense mutations, in which a codon is changed to a premature stop codon that results in truncation of the resulting protein, and the nonstop mutations, in which a stop codon erasement results in a longer, nonfunctional protein. Missense mutations can render the resulting protein nonfunctional, and such mutations are responsible for human diseases such as Epidermolysis bullosa, sickle-cell disease, SOD1 mediated ALS, and a substantial number of cancers. In the most common variant of sickle-cell d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GRIP1 (gene)
Glutamate receptor-interacting protein 1 is a protein that in humans is encoded by the ''GRIP1'' gene. Interactions GRIP1 (gene) has been shown to interact with: * GRM3, * GRIA2, * GRIA3, * GRIA4, * GRIK2, and * GRIK3 Glutamate receptor, ionotropic kainate 3 is a protein that in humans is encoded by the ''GRIK3'' gene. This gene encodes a protein that belongs to the ligand-gated ionic channel family. It can coassemble with either GRIK4 or GRIK5 to form heterome .... References Further reading * * * * * * * * * * * * * * External links * * {{gene-12-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microtubule
Microtubules are polymers of tubulin that form part of the cytoskeleton and provide structure and shape to eukaryotic cells. Microtubules can be as long as 50 micrometres, as wide as 23 to 27 nm and have an inner diameter between 11 and 15 nm. They are formed by the polymerization of a dimer of two globular proteins, alpha and beta tubulin into protofilaments that can then associate laterally to form a hollow tube, the microtubule. The most common form of a microtubule consists of 13 protofilaments in the tubular arrangement. Microtubules play an important role in a number of cellular processes. They are involved in maintaining the structure of the cell and, together with microfilaments and intermediate filaments, they form the cytoskeleton. They also make up the internal structure of cilia and flagella. They provide platforms for intracellular transport and are involved in a variety of cellular processes, including the movement of secretory vesicles, organell ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cerebral Cortex
The cerebral cortex, also known as the cerebral mantle, is the outer layer of neural tissue of the cerebrum of the brain in humans and other mammals. The cerebral cortex mostly consists of the six-layered neocortex, with just 10% consisting of allocortex. It is separated into two cortices, by the longitudinal fissure that divides the cerebrum into the left and right cerebral hemispheres. The two hemispheres are joined beneath the cortex by the corpus callosum. The cerebral cortex is the largest site of neural integration in the central nervous system. It plays a key role in attention, perception, awareness, thought, memory, language, and consciousness. The cerebral cortex is part of the brain responsible for cognition. In most mammals, apart from small mammals that have small brains, the cerebral cortex is folded, providing a greater surface area in the confined volume of the cranium. Apart from minimising brain and cranial volume, cortical folding is crucial for the brain ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arabidopsis Thaliana
''Arabidopsis thaliana'', the thale cress, mouse-ear cress or arabidopsis, is a small flowering plant native to Eurasia and Africa. ''A. thaliana'' is considered a weed; it is found along the shoulders of roads and in disturbed land. A winter annual with a relatively short lifecycle, ''A. thaliana'' is a popular model organism in plant biology and genetics. For a complex multicellular eukaryote, ''A. thaliana'' has a relatively small genome around 135 mega base pairs. It was the first plant to have its genome sequenced, and is a popular tool for understanding the molecular biology of many plant traits, including flower development and light sensing. Description ''Arabidopsis thaliana'' is an annual (rarely biennial) plant, usually growing to 20–25 cm tall. The leaves form a rosette at the base of the plant, with a few leaves also on the flowering stem. The basal leaves are green to slightly purplish in color, 1.5–5 cm long, and 2–10 mm broad, with an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microfibrils
A microfibril is a very fine fibril, or fiber-like strand, consisting of glycoproteins and cellulose. It is usually, but not always, used as a general term in describing the structure of protein fiber, e.g. hair and sperm tail. Its most frequently observed structural pattern is the 9+2 pattern in which two central protofibrils are surrounded by nine other pairs. Cellulose inside plants is one of the examples of non-protein compounds that are using this term with the same purpose. Cellulose microfibrils are laid down in the inner surface of the primary cell wall. As the cell absorbs water, its volume increases and the existing microfibrils separate and new ones are formed to help increase cell strength. Synthesis and function Cellulose is synthesized by cellulose synthase or Rosette terminal complexes which reside on a cells membrane. As cellulose fibrils are synthesized and grow extracellularly they push up against neighboring cells. Since the neighboring cell can not move easily ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitella
''Nitella'' is a genus of charophyte green algae in the family Characeae. Species The species in the genus include: *'' Nitella abyssinica'' A. Braun * '' Nitella acuminata'' A. Braun ex Wallman *'' Nitella aemula'' A. Braun * '' Nitella annandalei'' B.P. Pal * '' Nitella australiensis'' (F.M. Bailey) J.C. van Raam * '' Nitella axillaris'' A. Braun * '' Nitella axilliformis'' Imahori * '' Nitella capillaris'' (A.J.Krocker) J.Groves & G.R.Bullock-Webster * '' Nitella comptonii'' J. Groves * '' Nitella cristata'' A. Braun * '' Nitella diffusa'' A. Braun * '' Nitella flexilis'' (Linnaeus) C. Agardh * ''Nitella furcata'' (Roxburgh ex Bruzelius) C. Agardh * '' Nitella gelatinifera'' R.D. Wood * '' Nitella gelatinosa'' A. Braun * '' Nitella gloeostachys'' A. Braun * ''Nitella gracilens'' Morioka * ''Nitella gracilis'' (J.E.Smith) C.Agardh * ''Nitella gracillima'' T.F. Allen * ''Nitella haagenii'' J.C. van Raam * ''Nitella heterophylla'' A. Braun * ''Nitella hookeri'' A. Braun * ''N ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nutation (botany)
Nutation refers to the bending movements of stems, roots, leaves and other plant organs caused by differences in growth in different parts of the organ. Circumnutation refers specifically to the circular movements often exhibited by the tips of growing plant stems, caused by repeating cycles of differences in growth around the sides of the elongating stem. Nutational movements are usually distinguished from 'variational' movements caused by temporary differences in the water pressure inside plant cells (turgor). Simple nutation occurs in flat leaves and flower petals, caused by unequal growth of the two sides of the surface. For example, in young leaf buds the outer surface of each leaflet grows faster, causing it to curve over its neighbors and form a compact bud. As the bud expands, growth becomes more rapid on the inner surface of the leaves, causing the bud to open and the leaves to flatten out. Similar inequality of growth, but more sharply localized, leads to the folding a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cell (biology)
The cell is the basic structural and functional unit of life forms. Every cell consists of a cytoplasm enclosed within a membrane, and contains many biomolecules such as proteins, DNA and RNA, as well as many small molecules of nutrients and metabolites.Cell Movements and the Shaping of the Vertebrate Body in Chapter 21 of Molecular Biology of the Cell '' fourth edition, edited by Bruce Alberts (2002) published by Garland Science. The Alberts text discusses how the "cellular building blocks" move to shape developing embryos. It is also common to describe small molecules such as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
