enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Biosphere - Wikipedia

    en.wikipedia.org/wiki/Biosphere

    Geochemists define the biosphere as being the total sum of living organisms (the "biomass" or "biota" as referred to by biologists and ecologists). In this sense, the biosphere is but one of four separate components of the geochemical model, the other three being geosphere, hydrosphere, and atmosphere.

  3. Life - Wikipedia

    en.wikipedia.org/wiki/Life

    Living things are composed of biochemical molecules, formed mainly from a few core chemical elements. All living things contain two types of large molecule, proteins and nucleic acids, the latter usually both DNA and RNA: these carry the information needed by each species, including the instructions to make each type of protein. The proteins ...

  4. Timeline of the evolutionary history of life - Wikipedia

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

    At long irregular intervals, Earth's biosphere suffers a catastrophic die-off, a mass extinction, [9] often comprising an accumulation of smaller extinction events over a relatively brief period. [10] The first known mass extinction was the Great Oxidation Event 2.4 billion years ago, which killed most of the planet's obligate anaerobes.

  5. Outline of life forms - Wikipedia

    en.wikipedia.org/wiki/Outline_of_life_forms

    A life form (also spelled life-form or lifeform) is an entity that is living, [1] [2] such as plants , animals , and fungi . It is estimated that more than 99% of all species that ever existed on Earth, amounting to over five billion species, [3] are extinct. [4] [5] Earth is the only celestial body known to harbor life forms. No form of ...

  6. Biogeochemical cycle - Wikipedia

    en.wikipedia.org/wiki/Biogeochemical_cycle

    The living factors of the planet can be referred to collectively as the biosphere. All the nutrients — such as carbon, nitrogen, oxygen, phosphorus, and sulfur — used in ecosystems by living organisms are a part of a closed system; therefore, these chemicals are recycled instead of being lost and replenished constantly such as in an open ...

  7. Biocentrism (ethics) - Wikipedia

    en.wikipedia.org/wiki/Biocentrism_(ethics)

    Biocentrism (from Greek βίος bios, "life" and κέντρον kentron, "center"), in a political and ecological sense, as well as literally, is an ethical point of view that extends equal inherent value to all living things. [1] It is an understanding of how the earth works, particularly as it relates to its biosphere or biodiversity.

  8. Climate system - Wikipedia

    en.wikipedia.org/wiki/Climate_system

    The five components of the climate system all interact. They are the atmosphere, the hydrosphere, the cryosphere, the lithosphere and the biosphere. [1]: 1451 Earth's climate system is a complex system with five interacting components: the atmosphere (air), the hydrosphere (water), the cryosphere (ice and permafrost), the lithosphere (earth's upper rocky layer) and the biosphere (living things).

  9. Natural environment - Wikipedia

    en.wikipedia.org/wiki/Natural_environment

    A diverse variety of living organisms (life forms) can be found in the biosphere on Earth, and properties common to these organisms—plants, animals, fungi, protists, archaea, and bacteria—are a carbon- and water-based cellular form with complex organization and heritable genetic information.