how do we gain energy for daily routine work from the food we eat? Explian on the basis of the reactions taking place.Please help.

The reaction you are referring to is aerobic cellular
respiration. Respiration begins with an organic compound with stored chemical energy
such as glucose. Producers like green plants, capture solar energy and combine carbon
dioxide and water in their chloroplasts to produce the organic compound glucose. By
consuming food and digesting it, the endproducts of digestion are absorbed into the
circulating blood and transported to the cells. Glucose enters the cell and in the
cytoplasm and then in the mitochondria, cellular respiration occurs. Using enzymes and
coenzymes, the reaction results in the break-down of glucose in the presence of oxygen,
to yield 36 A.T.P. and carbon dioxide and water as waste products. A.T.P. is adenosine
triphosphate, a high- energy compound that cells use as energy currency for life
processes.