Answer:
The reactants of photosynthesis are, for the most part, the products of respiration, and the reactants of respiration are the products of photosynthesis.
Step-by-step explanation:
Photosynthesis needs the reactants carbon dioxide, water, nutrients (from the soil), and energy (from sunlight). It produces fuels like glucose, in addition to oxygen (O2).
Cellular respiration needs the reactants of fuels like glucose, in addition to oxygen. It yields ATP, carbon dioxide, and water.