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  2. Biogenic substance - Wikipedia

    en.wikipedia.org/wiki/Biogenic_substance

    Crude oil, a transformed biogenic substance Natural gum, a secretion from Hevea brasiliensis. A biogenic substance is a product made by or of life forms. While the term originally was specific to metabolite compounds that had toxic effects on other organisms, [1] it has developed to encompass any constituents, secretions, and metabolites of plants or animals. [2]

  3. Endolith - Wikipedia

    en.wikipedia.org/wiki/Endolith

    Endolith lifeform found inside an Antarctic rock. An endolith or endolithic is an organism (archaeon, bacterium, fungus, lichen, algae, sponge, or amoeba) that is able to acquire the necessary resources for growth in the inner part of a rock, [1] mineral, coral, animal shells, or in the pores between mineral grains of a rock.

  4. Skolithos - Wikipedia

    en.wikipedia.org/wiki/Skolithos

    The famous "Pipe Rock" of northwest Scotland is a well-known example of Skolithos. The 'pipes' that give the rock its name are closely packed straight Skolithos tubes that were presumably made by a worm-like organism. [13] The Pipe Rock can be found in the Stack of Glencoul region beneath the Moine Thrust Belt, Scotland. [14]

  5. Timeline of the evolutionary history of life - Wikipedia

    en.wikipedia.org/wiki/Timeline_of_the...

    Possible remains of biotic life were found in 4.1 billion-year-old rocks in Western Australia. [26] [27] Probable origin of life. 4000 Ma Formation of a greenstone belt of the Acasta Gneiss of the Slave craton in northwest Canada - the oldest known rock belt. [28] 3900–2500 Ma Cells resembling prokaryotes appear. [29]

  6. Gastrolith - Wikipedia

    en.wikipedia.org/wiki/Gastrolith

    A gastrolith, also called a stomach stone or gizzard stone, is a rock held inside a gastrointestinal tract. Gastroliths in some species are retained in the muscular gizzard and used to grind food in animals lacking suitable grinding teeth. In other species the rocks are ingested and pass through the digestive system and are frequently replaced.

  7. Endogeny (biology) - Wikipedia

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

    For example, endogenous substances, and endogenous processes are those that originate within a living system (e.g. an organism or a cell). For instance, estradiol is an endogenous estrogen hormone produced within the body, whereas ethinylestradiol is an exogenous synthetic estrogen, commonly used in birth control pills .

  8. Chiton - Wikipedia

    en.wikipedia.org/wiki/Chiton

    They live on hard surfaces, such as on or under rocks, or in rock crevices. Some species live quite high in the intertidal zone and are exposed to the air and light for long periods. Most species inhabit intertidal or subtidal zones, and do not extend beyond the photic zone , but a few species live in deep water, as deep as 6,000 m (20,000 ft).

  9. Marine biogenic calcification - Wikipedia

    en.wikipedia.org/wiki/Marine_biogenic_calcification

    Marine biogenic calcification is the production of calcium carbonate by organisms in the global ocean.. Marine biogenic calcification is the biologically mediated process by which marine organisms produce and deposit calcium carbonate minerals to form skeletal structures or hard tissues.