When.com Web Search

Search results

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

    en.wikipedia.org/wiki/Cellular_respiration

    Nutrients that are commonly used by animal and plant cells in respiration include sugar, amino acids and fatty acids, and the most common oxidizing agent is molecular oxygen (O 2). The chemical energy stored in ATP (the bond of its third phosphate group to the rest of the molecule can be broken allowing more stable products to form, thereby ...

  3. Respiration (physiology) - Wikipedia

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

    Although physiologic respiration is necessary to sustain cellular respiration and thus life in animals, the processes are distinct: cellular respiration takes place in individual cells of the organism, while physiologic respiration concerns the diffusion and transport of metabolites between the organism and the external environment.

  4. Dioxygen in biological reactions - Wikipedia

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

    Green algae and cyanobacteria in marine environments provide about 70% of the free oxygen produced on earth. [1] [need quotation to verify] The remainder is produced by terrestrial plants, although, for example, almost all oxygen produced in tropical forests is consumed by organisms living there. [2] A simplified overall formula for ...

  5. Metabolism - Wikipedia

    en.wikipedia.org/wiki/Metabolism

    Metabolism (/ m ə ˈ t æ b ə l ɪ z ə m /, from Greek: μεταβολή metabolē, "change") is the set of life-sustaining chemical reactions in organisms.The three main functions of metabolism are: the conversion of the energy in food to energy available to run cellular processes; the conversion of food to building blocks of proteins, lipids, nucleic acids, and some carbohydrates; and the ...

  6. Homeostasis - Wikipedia

    en.wikipedia.org/wiki/Homeostasis

    The kidneys measure the oxygen content rather than the partial pressure of oxygen in the arterial blood. When the oxygen content of the blood is chronically low, oxygen-sensitive cells secrete erythropoietin (EPO) into the blood. [53] The effector tissue is the red bone marrow which produces red blood cells (RBCs, also called erythrocytes).

  7. Oxygen - Wikipedia

    en.wikipedia.org/wiki/Oxygen

    The common allotrope of elemental oxygen on Earth is called dioxygen, O 2, the major part of the Earth's atmospheric oxygen (see Occurrence). O 2 has a bond length of 121 pm and a bond energy of 498 kJ/mol. [42] O 2 is used by complex forms of life, such as animals, in cellular respiration. Other aspects of O

  8. Bioenergetic systems - Wikipedia

    en.wikipedia.org/wiki/Bioenergetic_systems

    The energy for ATP resynthesis comes from three different series of chemical reactions that take place within the body. Two of the three depend upon the food eaten, whereas the other depends upon a chemical compound called phosphocreatine. The energy released from any of these three series of reactions is utilized in reactions that resynthesize ...

  9. Photosynthesis - Wikipedia

    en.wikipedia.org/wiki/Photosynthesis

    To use this stored chemical energy, an organism's cells metabolize the organic compounds through cellular respiration. Photosynthesis plays a critical role in producing and maintaining the oxygen content of the Earth's atmosphere, and it supplies most of the biological energy necessary for complex life on Earth. [2]