The reactants are the molecules involved in the reaction, and the products are the molecules that results from the reaction.
Photosynthesis converts carbon dioxide and water into oxygen and glucose.
Cellular respiration converts oxygen and glucose into water and carbon dioxide.
1. Photosynthesis occurs in plants | Cellular respiration occurs in plants and animals
2. Photosynthesis occurs in the chloroplast | Cellular respiration occurs in the mitochondria
3. In photosynthesis oxygen is a product | In cellular respiration it is a reactant
4. In photosynthesis carbon dioxide is a reactant | In cellular respiration it is a product
5. In photosynthesis water is a reactant | In cellular respiration water is a product
6. In photosynthesis glucose is a product | In cellular respiration glucose is a reactant
7. In photosynthesis the sunlight is a reactant | In cellular respiration sunlight is not involved, it happens anytime
8. In photosynthesis ATP is a product (from glucose breakdown) | In cellular respiration ATP is also a product (from glucose breakdown)