[Campbell Biology P.199] Cellular respiration uses glucose and O2, which have high levels of... | Practice Question

Cellular respiration uses glucose and O2, which have high levels of free energy, and releases CO2 and H2O, which have low levels of free energy. Based on this, which of the following statements about cellular respiration is correct?

  • A: It is non-spontaneous and endergonic.
  • B: It is spontaneous and exergonic.
  • C: It is spontaneous and endergonic.
  • D: It is non-spontaneous and exergonic.

Explanation

Cellular respiration breaks down glucose and oxygen, which are high in free energy, to produce carbon dioxide and water, which are low in free energy. This process involves a net release of free energy, making it an exergonic reaction. Exergonic reactions are by definition spontaneous, meaning they proceed without continuous energy input.