Question

photosynthesis and cellular respiration quiz
which of the following diagrams represents the correct cycling of gases?

Explanation:

Photosynthesis uses carbon - dioxide ($CO_2$) and water to produce oxygen ($O_2$) and glucose. Cellular respiration uses oxygen ($O_2$) to break down glucose and release carbon - dioxide ($CO_2$). So the correct gas - cycling has $CO_2$ going from respiration to photosynthesis and $O_2$ going from photosynthesis to respiration.

Answer:

The second option (where photosynthesis produces $O_2$ and respiration produces $CO_2$ in a cyclic manner)