Question

What percentage of the energy stored in glucose do humans recover by cellular respiration?

Answer 1

• Energy is generated by glyolysis and aerobic respiration which contributes to approximately 252kcal. This is only 37% of total energy of glucose i.e 686kcal/mol.

• According to the second law of thermodynamics all of the energy cannot be converted into work done i.e most of the energy is lost in the form of heat.

• So, there 63% of the energy present in glucose is lost in the form of heat and 37% of the total energy is used for cellular respiration