Final answer:
Carbohydrates and oxygen gas are the molecules produced in photosynthesis and used in cellular respiration.
Step-by-step explanation:
The molecules produced in photosynthesis and used in cellular respiration are carbohydrates and oxygen gas. Photosynthesis converts carbon dioxide and water into glucose (carbohydrates) and releases oxygen gas as a byproduct. These carbohydrates and oxygen gas are then used during cellular respiration to produce ATP (energy) through the process of breaking down glucose and combining it with oxygen.