Sap, cell

The anthocyanins are pH sensitive. Their color, in part, is deterrnined by the pH of the sap. Cyanin, for example, is red at pH 3, violet at 8, and blue at 11. However, there are other factors that affect the colors of the anthocyanins metallic salts, notably iron and aluminum, react with those anthocyanins containing vicinal hydroxy groups and produce highly colored complex compounds. Other factors are the colloidal condition of the cell sap and copigmentation (91). 

Zellen-bildung, /. cell formation, -faser, /. cell fiber. -faserstofF, m. cellulose, -filter, . revolving filter, -fliissigkeit, /. cell fluid, cell sap. 

Research into the copigmentation of anthocyanins started as early as 1913 when Willstatter and Everest determined the chemical structure of cyanidin 3-glucoside isolated from blue cornflowers and red roses, and attributed the color changes to different pH levels in cell saps. This theory, however, was questioned and in 1916, Willstatter and Zollinger,revising the previous work, proposed a new theory according to which the colors of the anthocyanins varied significantly by the effects... 

Vacuoles. Vacuoles have been identified in young bacteria. They are cavities in the protoplasm and contain a fluid known as cell sap. As the cells approach maturity, some of the water-soluble reserve food materials manufactured by the cell dissolve in the vacuoles. Insoluble constituents precipitate out as cytoplasmic inclusion bodies. 

That the cytoplasmic nucleic acid is present in the mitochondria, the micro-eomes, and the non-sedimentable cell-sap is also known.117 The nuclear ribonucleic acid has been reported to be associated with the nucleolus and the chromosomes.118 It is known, moreover, that the ribonucleic acids of the different parts of the cell are biochemically distinct, since they become labeled with P32 at different rates.119 In liver cells, the nuclear ribonucleic acid is also chemically distinct from the cytoplasmic material, since the two differ in composition.120 It is clear, therefore, that ribonucleic acids prepared from whole cells are likely to be mixtures of various molecular species. 

Vacuoles (70-78) are membrane-bound regions of the cell filled with cell sap. Vacuoles are surrounded by a tonoplast (vacuolar membranes) and are diverse with distinct functions. Most investigators believe that lysosomes and the plant vacuoles are the same. Vacuoles develop turgor pressure and maintain tissue rigidity. They are storage components for various metabolites such as reserve proteins in seeds and malic acid in crassulacean acid metabolism (CAM) plants. Vacuoles canremove toxic secondary products and are the sites of pigment deposition. 

The RNA of the cell is partly in the nucleus, partly in particles in the cytoplasm and partly as the soluble RNA of the cell sap many workers have shown that all these three fractions turn over differently. It is very important to realize in any discussion of the role of RNA in the cell that it is very inhomogeneous metabolically, and probably of more than one type. 

Cell sap inhibitor (154) Develops in rabbit cell sap fraction on... 

Polyfructoses are widely distributed as reserve food materials in plants. Usually these water-soluble polysaccharides can be extracted from their sources (e.g., tubers) without use of drastic reagents, since they are found in solution in cell sap. 

However, during the most active phase of heme synthesis in maturing erythroid cells, there is a marked shift in the localization of cellular iron from a membrane bound pool to the cytosol (78). Moreover, as shown by Yoda and Israel (79), mitochondria incubated in cell sap or sucrose synthesize equivalent amounts of heme, but those in sucrose release only a small amount of heme to the surrounding medium. In other words, the release of heme from the mitochondria seems to depend on protein(s) in the suspending medium. Thus, the cytosol appears to facilitate the uptake of iron by the mitochondria as well as the release of heme from the mitochondria. 

Metalaxyl is clearly fungicidal i n vitro to a variety of phycomycetous fungi. Its activity in vivo may also be enhanced by stimulation of host plant defenses including hypersensitive cell death (104), accumulation of phytoalexins such as glyceollin (121), and cal lose encasement of hyphae (122) after fungal infection of metalaxy1-treated soybeans. However, the mi vivo concentration of the compound in cell sap may be sufficient for fungitoxicity alone to account for its protective activity (123). 

The relatively simple measurement of the volumes of pea chloroplasts for various external osmotic pressures can yield a considerable amount of information about the organelles. If we measure the volume of the isolated chloroplasts at the same osmotic pressure as in the cytosol, we can determine the chloroplast volume that occurs in the plant cell. Cell sap expressed from young pea leaves can have an osmotic pressure of 0.70 MPa such sap comes mainly from the central vacuole, but because we expect n05 10801 to be essentially equal to nvacuole (Eq. 2.14), nce11 8ap is about the same as n05 10801 (some uncertainty exists because during extraction the cell sap can come into contact with water in the cell walls). At an external osmotic pressure of 0.70 MPa (indicated by an arrow and dashed vertical line in Fig. 2-11), pea chloroplasts have a volume of 29 pm3 when isolated from illuminated plants and 35 pm3 when isolated from plants in the dark (Fig. 2-11). Because these volumes occur at approximately the same osmotic pressure as found in the cell, they are presumably reliable estimates of pea chloroplast volumes in vivo. 

It suffices to know all the parameters (pressure, temperature and amounts of the components) but one to have a multiphase system fully defined (Sillen 1967), and this likewise holds for al the organs, the solution phases (cell sap, blood or xylem liquid, etc.) and one or two gas phases referring to an organism. Since and as long as all the phases coexist, the number of degrees of freedom F in a multiphase system consisting of K components and P phases will be... 

Agavose is found in the cell sap of the American Century Plant, Agave americana. 

Inulin.—Inulin is a carbohydrate isomeric with starch which has the chemical formula of C12H20O10. It is found dissolved in the cell sap of many plants, especially those of the Composite. If pieces of a plant part containing this substance be placed directly in alcohol for at least a week, then sectioned and mounted in alcohol, sphaero-crystals of inulin will be seen applied to the walls of the cells. When these sections are treated with a 25 per cent, solution of alpha naphthol and 2 or 3 drops of strong H2SO4, the sphaerocrystals will dissolve with a violet color. Fehling s solution is not reduced by inulin. 

Salicin.—Salicin is a glucoside occurring in the cell sap of the bark and leaves of the Willows and Poplars. Sections of these mounted in concentrated H2SO4 will show a red coloration in the cells containing this substance. If water be added a red powder is thrown down. 

Coniferin is a glucoside, occuring in the cell sap of the spruce, pine, and other plants of the Conifem. If sections containing- it are first treated with a solution of phenol and then with sulphuric acid, the cells containing it take on a deep blue color. 

Calcium Oxalate.—This substance, occurs in many plants always in the form of crystals. It is apparently formed by the reaction of salts of calcium, which have found their way into the cell sap from the soil, with oxalic acid which is manufactured by the plant. Calcium oxalate crystals dissolve readily in mineral acids without effervescence. They are insoluble in acetic acid or water. 

Membrane crystals are monoclinic prisms, each of which is surrounded by a wall or membrane. In the process of formation a crystal first is formed in the cell sap and then numerous oil globules make their appearance in the protoplasm surrounding it later some of the walls of the cell grow around the crystal and completely envelop it. 

The proteins insoluble in the cell-sap water are made soluble for translocation by means of proteolytic enzymes which change them into proteoses and peptones. 

Pigments.— These are substances which give color to various plant parts in which they are found. They occur either in special protoplasmic structures, as chloroplasts, chromoplasts or chroma-tophores, or dissolved in tjie cell sap. Of the pigments named the following will be considered Chlorophyll, Xanthophyll, Chromophyll, Etiolin, Anthocyanin, Phycocyanin, Phycophxin, and Phycoerythrin. 

Anthocyanins are applied to the blue, purple and red pigments which occur in the cell sap. The character of the color is claimed to be due to the alkalinity or acidity of the cell sap. 

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