Question

scientists say that photosynthesis and cellular respiration are reciprocal processes. why? a they use different cellular organelles. b the products of one process are the reactants of the other. c water is broken down in one process and formed in the other. d autotrophs are responsible for photosynthesis while heterotrophs are responsible for cellular respiration.

Explanation:

Photosynthesis produces glucose ($\ce{C6H12O6}$) and oxygen ($\ce{O2}$) using carbon dioxide ($\ce{CO2}$) and water ($\ce{H2O}$). Cellular respiration uses glucose and oxygen to produce carbon dioxide and water. So, the products of one are the reactants of the other. Option A is about organelles (chloroplasts for photosynthesis, mitochondria for respiration) but doesn't explain reciprocity. Option C only mentions water, not the overall relationship. Option D is incorrect as both autotrophs and heterotrophs do cellular respiration (autotrophs also do photosynthesis).

Answer:

B. The products of one process are the reactants of the other.