| MadSci Network: Botany |
You mother was partly right and partly wrong. She is right because plants do use oxygen all the time in cellular respiration. However, during the day they usually produce more oxygen in photosynthesis than they use in cellular respiration. Cellular respiration occurs in the mitochondria. Photosynthesis occurs in the plant's chloroplasts. Nonphotosynthetic tissues, such as underground roots, have no photosynthesis so depend exclusively on cellular respiration for energy. The dark reactions of photosynthesis do not accur at night and do not require oxygen. The dark reactions are a misnomer. A better term is the Calvin cycle, which occurs in the light because it uses energy captured in the light reactions of photosynthesis. Indoor plants would not significantly deplete the oxygen in a room. A single person is going to use much more oxygen than a few houseplants. Normal rooms are not airtight so there will also be air exchange. I doubt there has ever been a case where someone suffocated from lack of oxygen in a normal bedroom, with or without plants. Indoor suffocation is caused by fires or faulty heaters that produce carbon monoxide gas. References Is it true that having plants in the room will make you short of oxygen? Plant Respiration Photosynthesis and Respiration
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