Here is the chemical equation of photosynthesis

$$CO_2 + H_{2}O \longrightarrow C_{6}H_{12}O_{6} + O_2 $$

We see that the water is in reactant side of the equation. By the way, It ought to be catabolic reaction. However, It seems anabolic reaction on my textbook.

  • What should we think for this reaction?

  • How do we get If energy turned out in product side of the equation?

  • Why isn't photosynthesis catabolic reaction?

  • 1
    $\begingroup$ How do you define catabolic reactions in the first place? From what I see, the only thing I could say is "water on the reactant side != hydrolysis" $\endgroup$ Nov 2 '17 at 19:39
  • 1
    $\begingroup$ @another'Homosapien' That's my bad. $\endgroup$ Nov 3 '17 at 5:10
  • 2
    $\begingroup$ Possible duplicate of Catabolic and Anabolic Reactions $\endgroup$
    – rotaredom
    Nov 3 '17 at 18:37

Catabolic reactions are those that make larger/more complex molecules into those that are smaller/less complex, releasing energy.

Anabolic reactions are those that makes smaller/less complex molecules into those that are larger/more complex, costing energy.

Photosynthesis takes two of the least complex molecules from the perspective of biology, carbon dioxide and water, and forms glucose which is high-energy and complex - this is clearly an anabolic reaction.

The only way I can interpret your question is that you were misunderstanding the definitions of catabolic and anabolic.


Not the answer you're looking for? Browse other questions tagged or ask your own question.