When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. Prothallus - Wikipedia

    en.wikipedia.org/wiki/Prothallus

    Prothallus of the tree fern Dicksonia antarctica (note new moss plants for scale) Spore-bearing plants , like all plants, go through a life-cycle of alternation of generations . The fully grown sporophyte , what is commonly referred to as the fern , produces genetically unique spores in the sori by meiosis .

  3. Respiratory system - Wikipedia

    en.wikipedia.org/wiki/Respiratory_system

    The blood leaving the alveolar capillaries and is eventually distributed throughout the body therefore has a partial pressure of oxygen of 13–14 kPa (100 mmHg), and a partial pressure of carbon dioxide of 5.3 kPa (40 mmHg) (i.e. the same as the oxygen and carbon dioxide gas tensions as in the alveoli). [6]

  4. Lung - Wikipedia

    en.wikipedia.org/wiki/Lung

    [106] [107] Blood or air with a high oxygen content is shown in red; oxygen-poor air or blood is shown in various shades of purple-blue. The lungs of birds are relatively small, but are connected to eight or nine air sacs that extend through much of the body, and are in turn connected to air spaces within the bones. On inhalation, air travels ...

  5. Breathing - Wikipedia

    en.wikipedia.org/wiki/Breathing

    Real-time magnetic resonance imaging of the human thorax during breathing X-ray video of a female American alligator while breathing. Breathing (spiration [1] or ventilation) is the rhythmical process of moving air into and out of the lungs to facilitate gas exchange with the internal environment, mostly to flush out carbon dioxide and bring in oxygen.

  6. Respiration (physiology) - Wikipedia

    en.wikipedia.org/wiki/Respiration_(physiology)

    In physiology, respiration is the transport of oxygen from the outside environment to the cells within tissues, and the removal of carbon dioxide in the opposite direction to the environment by a respiratory system.

  7. Human body - Wikipedia

    en.wikipedia.org/wiki/Human_body

    The human body is the entire structure of a human being. It is composed of many different types of cells that together create tissues and subsequently organs and then organ systems. The external human body consists of a head, hair, neck, torso (which includes the thorax and abdomen), genitals, arms, hands, legs, and feet.

  8. Exhalation - Wikipedia

    en.wikipedia.org/wiki/Exhalation

    The main reason for exhalation is to rid the body of carbon dioxide, which is the waste product of gas exchange in humans. Air is brought into the lungs through inhalation. Diffusion in the alveoli allows for the exchange of O 2 into the pulmonary capillaries and the removal of CO 2 and other gases from the pulmonary capillaries to be exhaled ...

  9. 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.