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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, petrifaction or 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. Diagenesis - Wikipedia

    en.wikipedia.org/wiki/Diagenesis

    Permineralization in vertebra from Valgipes bucklandi Diagenesis ( / ˌ d aɪ . ə ˈ dʒ ɛ n ə s ɪ s / ) is the process that describes physical and chemical changes in sediments first caused by water-rock interactions, microbial activity, and compaction after their deposition .

  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. 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    Petrifaction is the result of a tree or tree-like plants having been replaced by stone via a mineralization process that often includes permineralization and replacement.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 ...

  7. Anatomy of the human heart - Wikipedia

    en.wikipedia.org/wiki/Anatomy_of_the_human_heart

    The heart is a muscular organ situated in the mediastinum.It consists of four chambers, four valves, two main arteries (the coronary arteries), and the conduction system. The left and right sides of the heart have different functions: the right side receives de-oxygenated blood through the superior and inferior venae cavae and pumps blood to the lungs through the pulmonary artery, and the left ...

  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. Clinical death - Wikipedia

    en.wikipedia.org/wiki/Clinical_death

    However, the injured cells do not actually die until hours after resuscitation. [8] This delayed death can be prevented in vitro by a simple drug treatment even after 20 minutes without oxygen. [9] In other areas of the brain, viable human neurons have been recovered and grown in culture hours after clinical death. [10]