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Symplast
The symplast of a plant is the region enclosed by the cell membranes, within which water and solutes can diffuse freely. By contrast the apoplast is any fluid-filled space within the cell wall and extracellular space. Neighbouring cells are interconnected by microscopic channels known as plasmodesmata that traverse the cell walls. These channels, allow the flow of small molecules such as sugars, amino acids, and ions between cells (from the inner part of one cell to the inner part of the next cell). Larger molecules, including transcription factors and plant viruses, can also be transported through with the help of actin structures. The symplast allows direct cytoplasm-to-cytoplasm flow of water and other nutrients along concentration gradients. In particular, symplastic flow is used in the root systems to bring in nutrients from soil. Nutrient solutes move in this way through three skin layers of the roots: from cells of the ''epidermis'', the outermost layer, through the ' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apoplast And Symplast Pathways
The ''apoplast '' is the extracellular space outside of plant cell membranes, especially the fluid-filled cell walls of adjacent cells where water and dissolved material can flow and diffuse freely. Fluid and material flows occurring in any extracellular space are called ''apoplastic'' flow or apoplastic transport. The apoplastic pathway is one route by which water and solutes are transported and distributed to different places through tissues and organs, contrasting with the symplastic pathway. To prevent uncontrolled leakage to unwanted places, in certain areas there are barriers to the apoplastic flow: in roots the Casparian strip has this function Outside the plant epidermis of aerial plant parts is a protective waxy film called plant cuticle that protects against drying out, but also waterproofs the plant against external water. The apoplast is important for all the plant's interaction with its environment: The main carbon source (carbon dioxide) needs to be solubiliz ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Casparian Strip
The Casparian strip is a band-like thickening in the center of the root endodermis (radial and tangential walls of endodermal cells) of vascular plants (Pteridophytes and Spermatophytes). The composition of the region is mainly suberin, lignin and some structural proteins, which are capable of reducing the diffusive apoplastic flow of water and solutes into the stele, its width varies between species. In the root, the Casparian strip is embedded within the cell wall of endodermal cells in the non-growing region of the root behind the root tip.Taiz, L., Zeiger, Eduardo, Møller, Ian Max, & Murphy, Angus. (2015). Plant physiology and development (Sixth ed.). Here, the Casparian strip serves as a boundary layer separating the apoplast of the cortex from the apoplast of the vascular tissue thereby blocking diffusion of material between the two. This separation forces water and solutes to pass through the plasma membrane via a symplastic route in order to cross the endodermis layer. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protoplast
Protoplast (), is a biology, biological term coined by Johannes von Hanstein, Hanstein in 1880 to refer to the entire cell, excluding the cell wall. Protoplasts can be generated by stripping the cell wall from plant, bacterium, bacterial, or fungus, fungal cells by mechanical, chemical or enzymatic means. Protoplasts differ from spheroplasts in that their cell wall has been completely removed. Spheroplasts retain part of their cell wall. In the case of Gram-negative bacterial spheroplasts, for example, the peptidoglycan component of the cell wall has been removed but the bacterial outer membrane, outer membrane component has not. Enzymes for the preparation of protoplasts Cell walls are made of a variety of polysaccharides. Protoplasts can be made by degrading cell walls with a mixture of the appropriate polysaccharide-degrading enzymes: During and subsequent to digestion of the cell wall, the protoplast becomes very sensitive to osmosis, osmotic stress. This means cell wal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polar Auxin Transport
Polar auxin transport is the regulated transport of the plant hormone auxin in plants. It is an active process, the hormone is transported in cell-to-cell manner and one of the main features of the transport is its asymmetry and directionality ( polarity). The polar auxin transport functions to coordinate plant development; the following spatial auxin distribution underpins most of plant growth responses to its environment and plant growth and developmental changes in general. In other words, the flow and relative concentrations of auxin informs each plant cell where it is located and therefore what it should do or become. Chemiosmotic model Polar auxin transport (PAT) is directional and active flow of auxin molecules through the plant tissues. The flow of auxin molecules through the neighboring cells is driven by carriers (''type of membrane transport protein'') in the cell-to-cell fashion (from one cell to other cell and then to the next one) and the direction of the flow i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plant Sap
Sap is a fluid transported in the xylem cells (vessel elements or tracheids) or phloem sieve tube elements of a plant. These cells transport water and nutrients throughout the plant. Sap is distinct from latex, resin, or cell sap; it is a separate substance, separately produced, and with different components and functions. Honeydew (secretion), Insect honeydew is called sap, particularly when it falls from trees, but is only the remains of eaten sap and other plant parts. Types of sap Saps may be broadly divided into two types: xylem sap and phloem sap. Xylem sap Xylem sap (pronounced ) consists primarily of a watery solution of plant hormone, hormones, dietary mineral, mineral elements and other nutrients. Transport of sap in xylem is characterized by movement from the roots toward the leaf, leaves. Over the past century, there has been some controversy regarding the mechanism of xylem sap transport; today, most plant scientists agree that the cohesion-tension theory be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ernst Münch
Ernst Münch (26 November 1876 – 9 October 1946) was a German plant physiologist who proposed the pressure flow hypothesis in 1930. He studied in Aschaffenburg, and then in Munich Munich is the capital and most populous city of Bavaria, Germany. As of 30 November 2024, its population was 1,604,384, making it the third-largest city in Germany after Berlin and Hamburg. Munich is the largest city in Germany that is no ... with Robert Hartig. He worked in a number of fields including forest pathology, resin production, and fungi. He is best known for the phloem pressure flow hypothesis. Works * ''Untersuchungen über Immunität und Krankheitsempfänglichkeit der Holzpflanzen'', Dissertation, Ludwigsburg 1909 (doctorate thesis) * ''Die Stoffbewegungen in der Pflanze'', Jena 1930 * ''Beiträge zur Forstpflanzenzüchtung. Versuche einer Auslesezüchtung durch Einzelstamm-Absaaten bei Fichte. Weitere Beiträge zur Forstpflanzenzüchtung'' us dem wissenschaftlichen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Johannes Von Hanstein
Johannes Ludwig Emil Robert von Hanstein (15 May 1822 – 27 August 1880) was a German botanist who was a native of Potsdam. He attended classes at the ''Gärtnerlehranstalt'' (Institute of Horticulture) in Potsdam, and later studied sciences in Berlin, obtaining his doctorate in 1848. In 1855 he was a lecturer of botany at the University of Berlin, and six years later became curator of the royal herbarium. In 1865 he was appointed professor of botany at the University of Bonn and director of the botanical garden. Hanstein is remembered for studies in plant anatomy and morphology. In 1868 he introduced the " histogen theory" to explain shoot apex behaviour in plants. With his close friend, Nathanael Pringsheim (1823–1894), he conducted pioneer research on the fertilization process in ferns. The plant genus '' Hansteinia'' of the family Acanthaceae is named after him. Gallery File:Capsella bursa-pastoris, kiembol (Hanstein).jpg, ''Capsella bursa-pastoris'' drawing by Johann ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eduard Strasburger
Eduard Adolf Strasburger (1 February 1844 – 18 May 1912) was a Polish- German professor and one of the most famous botanists of the 19th century. He discovered mitosis in plants. Life Eduard Strasburger was born in Warsaw, Congress Poland, the son of Anna Karoline (von Schütz) and Eduard Gottlieb Strasburger (1803–1874)."Eduard STRASBURGER ward 1844 in Warschau als ältester Sohn des Kaufmannes EDUARD GOTTLIEB STRASBURGER und seiner Frau ANNA KAROLINE geb. V. SCHÜTZ geboren. Die Vorfahren beider Eltern waren seinerzeit mit den sächsischen Königen nach Polen gegangen.Nachrufe. Eduard Strasburger. Von Gr. Karsten zobodat.atKlaus Oskar Leyde: Strasburger. In: Deutsches Geschlechterbuch Band 207 (56. Allgemeiner Band), C. A. Starke Verlag, Limburg 1998, S. 227–242. In 1870, he married Alexandra Julia ("Alexandrine") Wertheim (1847–1902), they had two children: Anna (1870–1942) and Julius (1871–1934). Strasburger studied biological sciences in Paris, Bonn and Je ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Huntia (journal)
''Huntia'' is a peer-reviewed scientific journal published by the Hunt Institute for Botanical Documentation, a research division of the Carnegie Mellon University. In continuous publication since 1964, this journal is the institute's scholarly journal of botanical history. The journal is published irregularly in one or more numbers per volume of approximately 200 pages by Hunt Institute. Huntia was established by the American botanist George H.M. Lawrence, who was the founding director of the Hunt Institute. Volumes 1 to 7, was issued in 14 volumes, large octavo (folded paper) they were paperback apart from Volume 2 which was clothbound. Vol.2 was reviewed by botanist William C. Steere in June 1966. He noted "outstanding typography, high quality of illustrations and paper, the beautiful style and manufacture all indicate the high standards we have come to anticipate in publications of the Hunt Botanical Library". There was a big gap in publication of the journal when Lawrence ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plasmodesmata
Plasmodesmata (singular: plasmodesma) are microscopic channels which traverse the cell walls of plant cells and some algal cells, enabling transport and communication between them. Plasmodesmata evolved independently in several lineages, and species that have these structures include members of the Charophyceae, Charales, Coleochaetales and Phaeophyceae (which are all algae), as well as all embryophytes, better known as land plants. Unlike animal cells, almost every plant cell is surrounded by a polysaccharide cell wall. Neighbouring plant cells are therefore separated by a pair of cell walls and the intervening middle lamella, forming an extracellular domain known as the apoplast. Although cell walls are permeable to small soluble proteins and other solutes, plasmodesmata enable direct, regulated, symplastic transport of substances between cells. There are two forms of plasmodesmata: primary plasmodesmata, which are formed during cell division, and secondary plasmodesma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
