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Workshop 5

2. Respiration

energy releaseScientists use the word "respiration" in two senses. One meaning for respiration is the intake of oxygen and the exhaling of carbon dioxide that we also know as "breathing." The second meaning, which is more relevant to understanding energy, is the cellular process by which food molecules are oxidized, releasing energy and liberating carbon dioxide as a waste product.

Respiration Facts
  • Respiration is a very complex process. It involves many steps—too many to include in the video program—so here's a missing step:

    When energy rich molecular bonds from the simple sugar glucose are broken, a molecule called ATP (adenosinetriphosphate)—the "universal" fuel for life processes—transfers the energy from the glucose to all cells of the body.

    Remember, during respiration, carbon dioxide is produced as a waste product:
    (CH2O) + O2 -> CO2 + H2O

  • We can think of respiration as the reverse of photosynthesis. Energy is stored chemically during photosynthesis and transferred chemically to ATP during respiration. Photosynthesis uses carbon dioxide (CO2) and produces free oxygen (O2) as a waste product. Respiration uses free oxygen and produces carbon dioxide as a waste product.

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