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Free Energy Efficiency

APBIO-LQPHW5

The incremental oxidation of one molecule of glucose during cell respiration produces 30 molecules of ATP according the balanced equation:

$$C_{6}H_{12}O_{6} + 6O_{2} + 30ADP + 30P_{i} \rightarrow 6{H}_{2}O + 6C{O}_{2} + 30ATP$$

ATP is then hydrolyzed by cells for a variety of biochemical processes.

Changes in free energy between glucose oxidation and ATP hydrolysis were compared. The table below illustrates the data collected:

Reaction Change in Free Energy ($\Delta G$)
Glucose Oxidation -686 kcal/mol
ATP Hydrolysis -7 kcal/mol

$ \ $

Which of the following statements provides the BEST explanation for the disparity between energy produced from the oxidation of 1 mole of glucose versus the hydrolysis of 30 moles of ATP?

A

The efficiency of total ATP production from one mole of glucose is almost 100% because cells make 30 molecules of ATP for every molecule of glucose.

B

The efficiency of total ATP production from one mole of glucose is about 50% because some of the energy is lost as a result of incomplete oxidation of glucose.

C

The efficiency of total ATP production from one mole of glucose is only about 1% because most of the energy is lost as heat.

D

The efficiency of total ATP production from one mole of glucose is only about 31% because most of the energy is lost as heat.