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  2. Ozone - Wikipedia

    en.wikipedia.org/wiki/Ozone

    According to the American Lung Association, the Denver–Aurora area is the 14th most ozone-polluted area in the U.S. [65] The problem of high ozone levels is not new to this area. In 2004, the EPA allotted the Denver Metro /North Front Range [ b ] as non-attainment areas per 1997's 8-hour ozone standard, [ 66 ] but later deferred this status ...

  3. Composition of the human body - Wikipedia

    en.wikipedia.org/wiki/Composition_of_the_human_body

    Parts-per-million cube of relative abundance by mass of elements in an average adult human body down to 1 ppm. About 99% of the mass of the human body is made up of six elements: oxygen, carbon, hydrogen, nitrogen, calcium, and phosphorus. Only about 0.85% is composed of another five elements: potassium, sulfur, sodium, chlorine, and magnesium ...

  4. Ground-level ozone - Wikipedia

    en.wikipedia.org/wiki/Ground-level_ozone

    [1] [2] Ozone is also an important constituent of the stratosphere, where the ozone layer (2 to 8 parts per million ozone) exists which is located between 10 and 50 kilometers above the Earth's surface. [3] The troposphere extends from the ground up to a variable height of approximately 14 kilometers above sea level.

  5. Reactive oxygen species - Wikipedia

    en.wikipedia.org/wiki/Reactive_oxygen_species

    In chemistry and biology, reactive oxygen species (ROS) are highly reactive chemicals formed from diatomic oxygen (O 2), water, and hydrogen peroxide. Some prominent ROS are hydroperoxide (H 2 O 2), superoxide (O 2 −), [1] hydroxyl radical (OH.), and singlet oxygen(1 O 2). [2] ROS are pervasive because they are readily produced from O 2 ...

  6. List of unsolved problems in biology - Wikipedia

    en.wikipedia.org/wiki/List_of_unsolved_problems...

    Decline in average human body temperature since the 19th century: Medical data suggests that the average body temperature has declined 0.6 °C since the 19th century. The cause is unclear although it has been suggested that it has some relation with reduced inflammation from reduced exposure to microorganisms.

  7. Trioxidane - Wikipedia

    en.wikipedia.org/wiki/Trioxidane

    The reverse reaction, the addition of singlet oxygen to water, typically does not occur in part due to the scarcity of singlet oxygen. In biological systems, however, ozone is known to be generated from singlet oxygen, and the presumed mechanism is an antibody-catalyzed production of trioxidane from singlet oxygen. [2]

  8. Body (biology) - Wikipedia

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

    The cell body is the part with the nucleus in it. The body of a dead person is also called a corpse or cadaver. The dead bodies of vertebrate animals and insects are sometimes called carcasses. The human body has a head, neck, torso, two arms, two legs and the genitals of the groin, which differ between males and females.

  9. Aerobic organism - Wikipedia

    en.wikipedia.org/wiki/Aerobic_organism

    Obligate aerobes need oxygen to grow. In a process known as cellular respiration, these organisms use oxygen to oxidize substrates (for example sugars and fats) and generate energy.