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  2. Concretion - Wikipedia

    en.wikipedia.org/wiki/Concretion

    Concretions in Torysh, Western Kazakhstan Concretions with lens shape from island in Vltava river, Prague, Czech Republic Marlstone aggregate concretion, Sault Ste. Marie, Michigan, United States A concretion is a hard and compact mass formed by the precipitation of mineral cement within the spaces between particles, and is found in sedimentary ...

  3. Coal ball - Wikipedia

    en.wikipedia.org/wiki/Coal_ball

    A coal ball is a type of concretion, varying in shape from an imperfect sphere to a flat-lying, irregular slab.Coal balls were formed in Carboniferous Period swamps and mires, when peat was prevented from being turned into coal by the high amount of calcite surrounding the peat; the calcite caused it to be turned into stone instead.

  4. Biological carbon fixation - Wikipedia

    en.wikipedia.org/wiki/Biological_carbon_fixation

    Cyanobacteria such as these carry out photosynthesis.Their emergence foreshadowed the evolution of many photosynthetic plants and oxygenated Earth's atmosphere.. Biological carbon fixation, or сarbon assimilation, is the process by which living organisms convert inorganic carbon (particularly carbon dioxide, CO 2) to organic compounds.

  5. Plant cell - Wikipedia

    en.wikipedia.org/wiki/Plant_cell

    Structure of a plant cell. Plant cells are the cells present in green plants, photosynthetic eukaryotes of the kingdom Plantae.Their distinctive features include primary cell walls containing cellulose, hemicelluloses and pectin, the presence of plastids with the capability to perform photosynthesis and store starch, a large vacuole that regulates turgor pressure, the absence of flagella or ...

  6. Xylem - Wikipedia

    en.wikipedia.org/wiki/Xylem

    Different plant species can have different root pressures even in a similar environment; examples include up to 145 kPa in Vitis riparia but around zero in Celastrus orbiculatus. [ 13 ] The primary force that creates the capillary action movement of water upwards in plants is the adhesion between the water and the surface of the xylem conduits.

  7. Pseudofossil - Wikipedia

    en.wikipedia.org/wiki/Pseudofossil

    One common example is when manganese oxides crystallize with a characteristic tree-like or dendritic pattern along a rock fracture. The formation of frost dendrites on a window is another common example of this crystal growth. Concretions are sometimes thought to be fossils, and occasionally one contains a fossil, but are generally not fossils ...

  8. Phytolith - Wikipedia

    en.wikipedia.org/wiki/Phytolith

    Plants affected by mosaic disease experienced a decrease in phytolith size. This is because the virus constricts overall plant growth and therefore phytolith growth as well. Contrastingly, plants affected with bacterial wilt disease resulted in much larger phytoliths but they were abnormally shaped. This could be due to the bacteria causing ...

  9. Organic matter - Wikipedia

    en.wikipedia.org/wiki/Organic_matter

    The organic matter in soil derives from plants, animals and microorganisms. In a forest, for example, leaf litter and woody materials fall to the forest floor. This is sometimes referred to as organic material. [9] When it decays to the point in which it is no longer recognizable, it is called soil organic matter.