In terms of producers, why is cellular respiration needed in addition to photosynthesis?
How are photosynthesis and cellular respiration similar
(Hint: look at the inputs/reactants and outputs/products)?
How are photosynthesis and cellular respiration different
(Hint: look at the inputs/reactants and outputs/products)?

Cellular respiration is needed to produce the carbon dioxide that is needed in photosynthesis to make oxygen.

Photosynthesis and cellular respiration are similar in the sense that they both carry out chemical reactions that release something into their environment.

Cellular respiration differs from photosynthesis because it used oxygen to make carbon dioxide, while photosynthesis uses carbon dioxide to make oxygen.

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