Final answer:
The efficiency of aerobic cellular respiration can be determined by comparing the energy released in the combustion of glucose (-2805 kJ/mol) to the energy used to form ATP from ADP (+57 kJ/mol). Aerobic respiration produces 36 to 38 ATP molecules per glucose molecule with an estimated efficiency of about 30% to 40%.
Step-by-step explanation:
Estimating the efficiency of aerobic cellular respiration of a molecule of glucose involves comparing the energy released by combustion of glucose to the energy required to form ATP from ADP. The energy of combustion of glucose is approximately -2805 kJ/mol. In the process of aerobic respiration, glucose is completely catabolized, and the chemical energy is converted into ATP. The formation of ATP from ADP requires around +57 kj/mol.
During aerobic cellular respiration, a total of 36 to 38 ATP molecules are produced from one molecule of glucose. This includes 2 ATP from glycolysis, 2 ATP (or GTP which convert to ATP) from the Krebs cycle, and approximately 32 ATP from the electron transport chain. Using the standard free energy change for the reaction (ΔGº), which is -687 kcal/mol glucose, and the cost of about 7.3 kcal to make each mole of ATP, you can estimate the number of ATP molecules produced after burning a mole of glucose. The efficiency of ATP production can be estimated by comparing the energy content in ATP generated to the total energy released during the combustion of glucose.
The overall equation for aerobic respiration is:
C6H12O6 + 6O2 + 32 ADP + 32 Pi ⇒ 6 CO2 + 6H2O + 32 ATP
Efficiency of Aerobic Respiration
The efficiency of ATP production is calculated by dividing the energy captured as ATP by the total energy released during glucose combustion. Given the amount of ATP produced and the energy content of glucose combustion, the efficiency rates are typically estimated to be between approximately 30% to 40%.