Which is true for both photosynthesis and cellular respiration? They require oxygen as a reactant. They require organelles. They require light energy from the sun. They require cells to use water.

The correct answer is 'they require organelles'. The mitochondria is the organelle that facilitates respiration and the chloroplast facilitates photosynthesis. Cellular respiration requires oxygen reactant, photosynthesis requires carbon dioxide. Photosynthesis requires light energy from the sun, not respiration. Water is used in photosynthesis while it is a byproduct in cellular respiration.