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Why Our Bodies Need Air

Just as air is needed to burn fossil fuels and release their energy (such as coal and natural gas), our bodies need air to burn the fuel of foodstuffs to release energy. What is it in air that is needed? .... OXYGEN

Why is this important for mitochondria?
Mitochondria are the cell components that use oxygen to liberate the chemical energy of foodstuffs and trap it in energy storage compounds that cells can use later.

What are mitochondria? and What do they do?

Mitochondria are the energy factories of the cells. Their job is to "burn" the fuel (which we get from food) and capture some of the energy in high
-energy chemical bonds that can be used later for various cell functions. See the diagram below. 

Process of Burning Energy Diagram

The diagram shows the structure of mitochondria and the relationships of the parts on the left. On the right, the diagram shows that sugars (glucose) are burned in two ways. Glucose, a sugar with 6 carbon atoms gets first gets broken down to a 3-carbon molecule (pyruvic acid) in a stage of chemical reactions called glycolysis.  This releases a little energy, but if oxygen is present, the pyruvic acid can then be burned to release a great deal of energy in a stage of chemical reactions called that give off carbon dioxide and water as waste products. In the presence of oxygen, the energy is extracted in a cycle of chemical reactions wherein the first molecule in the cycle gets re-built at the end of the cycle. We call this the "Krebs' cycle." Because the reactions cycle, the process sustains itself and continually produces energy as long as glucose and oxygen are present. Neat!


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