Photosynthesis is the process by which plants take in (use) Carbon-dioxide and water to make food (starch).
Photosynthesis:
[tex]CO_{2} + H_{2} 0 +sunlight ----> C_{6}H_{12}O_{6}+O_{2}[/tex]
Cellular respiration is the process in which cells use oxygen to break down starch into energy molecules and give out Carbon-dioxide.
Cellular respiration:
[tex]C_{6}H_{12}O_{6}+O_{2}----->CO_{2} + H_{2} 0 +energy[/tex]
So, in Photosynthesis, carbon-dioxide is taken in (used) and in cellular respiration, carbon-dioxide is thrown out (waste product)
