<span>This is the lack of glycogen being produced in the muscles and the liver. A person exercising has an amount of glycogen stored in these locations, and it is depleted while being used as a source of energy. When the person runs low (or out) of this sugar, the body has ways of making more through fat breakdown, but the person will begin to feel severe discomfort and lack of energy in the meantime until this energy is created.</span>
Natural Selection: <span>the process whereby organisms better adapted to their environment tend to survive and produce more offspring. hope this helps</span>
