enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. 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 ...

  3. Dioxygen in biological reactions - Wikipedia

    en.wikipedia.org/wiki/Dioxygen_in_biological...

    After being carried in blood to a body tissue in need of oxygen, O 2 is handed off from the heme group to monooxygenase, an enzyme that also has an active site with an atom of iron. [9] Monooxygenase uses oxygen for many oxidation reactions in the body. Oxygen that is suspended in the blood plasma equalizes into the tissue according to Henry's law.

  4. List of systems of the human body - Wikipedia

    en.wikipedia.org/wiki/List_of_systems_of_the...

    This is an accepted version of this page This is the latest accepted revision, reviewed on 24 February 2025. List of organ systems in the human body Part of a series of lists about Human anatomy General Features Regions Variations Movements Systems Structures Arteries Bones Eponymous Foramina Glands endocrine exocrine Lymphatic vessels Nerves Organs Systems Veins Muscles Abductors Adductors ...

  5. Biological roles of the elements - Wikipedia

    en.wikipedia.org/wiki/Biological_roles_of_the...

    A large fraction of the chemical elements that occur naturally on the Earth's surface are essential to the structure and metabolism of living things. Four of these elements (hydrogen, carbon, nitrogen, and oxygen) are essential to every living thing and collectively make up 99% of the mass of protoplasm. [1]

  6. Human iron metabolism - Wikipedia

    en.wikipedia.org/wiki/Human_iron_metabolism

    The human body needs iron for oxygen transport. Oxygen (O 2) is required for the functioning and survival of nearly all cell types. Oxygen is transported from the lungs to the rest of the body bound to the heme group of hemoglobin in red blood cells. In muscles cells, iron binds oxygen to myoglobin, which regulates its release.

  7. Cellular respiration - Wikipedia

    en.wikipedia.org/wiki/Cellular_respiration

    Aerobic respiration requires oxygen (O 2) in order to create ATP.Although carbohydrates, fats and proteins are consumed as reactants, aerobic respiration is the preferred method of pyruvate production in glycolysis, and requires pyruvate be transported the mitochondria in order to be oxidized by the citric acid cycle.

  8. Reactive oxygen species - Wikipedia

    en.wikipedia.org/wiki/Reactive_oxygen_species

    Several grams are produced per day in the human body within the mitochondria. [5] O 2 + e − → O − 2. Competing with its formation, superoxide is destroyed by the action of superoxide dismutases, enzymes that catalyze its disproportionation: 2 O − 2 + 2H + → O 2 + H 2 O 2. hydrogen peroxide (H 2 O 2) is also produced as a side product ...

  9. Red blood cell - Wikipedia

    en.wikipedia.org/wiki/Red_blood_cell

    Red blood cells (RBCs), referred to as erythrocytes (from Ancient Greek erythros ' red ' and kytos ' hollow vessel ', with -cyte translated as 'cell' in modern usage) in academia and medical publishing, also known as red cells, [1] erythroid cells, and rarely haematids, are the most common type of blood cell and the vertebrate's principal means of delivering oxygen (O 2) to the body tissues ...