Question

Which is correct about CO2 released in cellular respiration?

a. CO2 is released when glucose is converted to pyruvate in the mitochondrial matrix.
b. CO2 is formed when oxygen accepts electrons from the mitochondrial electron transport chain.
c. CO2 is what is left from the carbon chain of glucose after removal of H (electrons and H+).
d. CO2 is formed by extraction of electrons from water.

Answer 1

c. CO₂ is what is left from the carbon chain of glucose after removal of H (electrons and H+).

Step-by-step explanation:

During aerobic respiration, a glucose molecule is completely broken down into CO₂ and water. The complete chemical reaction is:

C₆H₁₂O₆ + 6 O₂ -------> 6 CO₂ + 6 H₂O + energy

The glucose is oxidized (loses protons and electrons) to CO₂, and oxygen is reduced (accepts electrons) forming water.

Some intermediate reactions take place in the cytoplasm, while others occur in the mitochondria, where ATP (energy) is produced during the electron transport chain.