How will photosynthesis and respiration keep you alive, and what do you need to do?

Explanation:

While cellular respiration releases carbon dioxide into the environment, photosynthesis pulls carbon dioxide out of the atmosphere. The exchange of carbon dioxide and oxygen during photosynthesis (Figure below) and cellular respiration worldwide helps to keep atmospheric oxygen and carbon dioxide at stable levels. (hopefully this helps)

if you know your abc's you should be able to get your answer or just use google