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  2. Permineralization - Wikipedia

    en.wikipedia.org/wiki/Permineralization

    Permineralization is a process of fossilization of bones and tissues in which mineral deposits form internal casts of organisms. Carried by water, these minerals fill the spaces within organic tissue. Because of the nature of the casts, permineralization is particularly useful in studies of the internal structures of organisms, usually of ...

  3. Petrifaction - Wikipedia

    en.wikipedia.org/wiki/Petrifaction

    Tree remains that have undergone petrifaction, as seen in Petrified Forest National Park. In geology, petrification (from Ancient Greek πέτρα (pétra) 'rock, stone') is the process by which organic material becomes a fossil through the replacement of the original material and the filling of the original pore spaces with minerals.

  4. Petrified wood - Wikipedia

    en.wikipedia.org/wiki/Petrified_wood

    Petrifaction is the result of a tree or tree-like plants having been replaced by stone via a mineralization process that often includes permineralization and replacement. [1] The organic materials making up cell walls have been replicated with minerals (mostly silica in the form of opal, chalcedony, or quartz). In some instances, the original ...

  5. Heart development - Wikipedia

    en.wikipedia.org/wiki/Heart_development

    The heart derives from embryonic mesodermal germ layer cells that differentiate after gastrulation into mesothelium, endothelium, and myocardium.Heart induction occurs in the anterior mesoderm during gastrulation through interactions with adjacent endoderm (both extra-embryonic and definitive) mediated primarily by endogenous inhibitors of WNT signaling such as DKK1.

  6. List of dates predicted for apocalyptic events - Wikipedia

    en.wikipedia.org/wiki/List_of_dates_predicted...

    This is an accepted version of this page This is the latest accepted revision, reviewed on 4 February 2025. This is a dynamic list and may never be able to satisfy particular standards for completeness. You can help by adding missing items with reliable sources. The Last Judgment by painter Hans Memling. In Christian belief, the Last Judgement is an apocalyptic event where God makes a final ...

  7. Blood vessel - Wikipedia

    en.wikipedia.org/wiki/Blood_vessel

    These deposit onto the arterial walls which are already partially occluded and build upon the blockage. [36] The most common disease of the blood vessels is hypertension or high blood pressure. This is caused by an increase in the pressure of the blood flowing through the vessels. Hypertension can lead to heart failure and stroke.

  8. Calcification - Wikipedia

    en.wikipedia.org/wiki/Calcification

    Calcification can manifest itself in many ways in the body depending on the location. In the pulpal structure of a tooth, calcification often presents asymptomatically, and is diagnosed as an incidental finding during radiographic interpretation. Individual teeth with calcified pulp will typically respond negatively to vitality testing; te

  9. Pericardium - Wikipedia

    en.wikipedia.org/wiki/Pericardium

    The pericardium (pl.: pericardia), also called pericardial sac, is a double-walled sac containing the heart and the roots of the great vessels. [1] It has two layers, an outer layer made of strong inelastic connective tissue (fibrous pericardium), and an inner layer made of serous membrane (serous pericardium).