Question

why is respiration known as exothermic process?

Answer 1

During respiration, glucose molecules are converted to other molecules in a series of steps. They finally end up as carbon dioxide and water. The reaction is exothermic because the C=O and O-H bonds in the products are so much more stable than the bonds in the reactants.

Answer 2

Starch item in the food item breaks down into glucose during digestion. Glucose is oxidized by the air breathed in during respiration into carbon dioxide and water along with evolution of heat energy. That is why respiration is considered as an exothermic reaction.