The correct interpretation is:
It shows that the same molecules used in photosynthesis are rearranged during cellular respiration, conserving matter and cycling molecules like glucose, oxygen, carbon dioxide, and water.
During cellular respiration, plants (and other organisms) take in glucose and oxygen to produce energy, and they release carbon dioxide and water as byproducts. This process highlights the continuity of matter in ecosystems, showing how the products of photosynthesis (glucose and oxygen) are utilized in cellular respiration, and in turn, how the byproducts (carbon dioxide and water) can be used again in photosynthesis. This cycle indicates that matter is constantly being recycled rather than permanently stored or lost.