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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. 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 ...

  4. Cell (biology) - Wikipedia

    en.wikipedia.org/wiki/Cell_(biology)

    Some eukaryotic cells (plant cells and fungal cells) also have a cell wall. Inside the cell is the cytoplasmic region that contains the genome (DNA), ribosomes and various sorts of inclusions. [2] The genetic material is freely found in the cytoplasm. Prokaryotes can carry extrachromosomal DNA elements called plasmids, which are usually circular.

  5. Sclereid - Wikipedia

    en.wikipedia.org/wiki/Sclereid

    Although sclereids are variable in shape, the cells are generally isodiametric, prosenchymatic, forked, or elaborately branched. They can be grouped into bundles, can form complete tubes located at the periphery, or can occur as single cells or small groups of cells within parenchyma tissues. An isolated sclereid cell is known as an idioblast.

  6. Ground tissue - Wikipedia

    en.wikipedia.org/wiki/Ground_tissue

    Sclerenchyma is the tissue which makes the plant hard and stiff. Sclerenchyma is the supporting tissue in plants. Two types of sclerenchyma cells exist: fibers cellular and sclereids. Their cell walls consist of cellulose, hemicellulose, and lignin. Sclerenchyma cells are the principal supporting cells in plant tissues that have ceased elongation.

  7. Cell biology - Wikipedia

    en.wikipedia.org/wiki/Cell_biology

    Cell biology (also cellular biology or cytology) is a branch of biology that studies the structure, function, and behavior of cells. [1] [2] All living organisms are made of cells. A cell is the basic unit of life that is responsible for the living and functioning of organisms. [3] Cell biology is the study of the structural and functional ...

  8. 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 ...

  9. 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.