I blame the plants
Do Plants Breathe?
The process of cells using oxygen and getting rid of carbon dioxide is called respiration. Plants have very small holes on the underneath of leaves, called stomata, which let the carbon dioxide and oxygen in and out in a process called diffusion.
Plant cells respire as well, using oxygen and getting rid of carbon dioxide. Plants also use carbon dioxide when they make food from the sunโs energy and this makes oxygen โ this is called photosynthesis. During the day, the plant cells photosynthesise more than they respire, so they get rid of more oxygen than carbon dioxide.
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