Question

In one or two sentences, explain how the chemical equation for cellular respiration shows that plants cycle matter.
Include the numbers of molecules and atoms involved to support your explanation. (2 points)

I

B

U

Answer 1

Cellular respiration: C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + energy — one glucose plus six O2 molecules yield six CO2 and six H2O molecules. This conserves atoms (6 C on both sides; 12 H on both sides; 18 O atoms on both sides: 6 O in C6H12O6 + 12 O in 6 O2 = 12 O in 6 CO2 + 6 O in 6 H2O), showing that plant matter is merely rearranged (carbon and hydrogen become CO2 and H2O) and can be cycled back into glucose by photosynthesis.