Answer 3: Plants need oxygen for the same reason you and I
do — without oxygen we can\’t convert the carbohydrates, fats, and proteins we eat into energy. We call this process respiration, and the formula for this sort of reaction is like this: So we breathe in oxygen and eat food, and we exhale carbon dioxide and excrete water. This exact same reaction goes on in every living cell, including all plant cells. But of course plants don\’t have to eat food, because they make their own food using photosynthesis. The formula for photosynthesis is basically this: You can see that this is basically the reverse of respiration, but plants convert the energy in sunlight into the chemical bonds of the sugar. When cells respire, they break those bonds and get the energy out of them. Anyway, you can see that photosynthesis produces oxygen as a waste product, so for the most part plants don\’t have to breathe in extra oxygen — they can just use the oxygen that they produce during photosynthesis. However, plants only perform photosynthesis in the green parts, like leaves and stems, but all plant cells need oxygen to respire. Cells in the leaves get plenty of oxygen from photosynthesis, but cells in the roots often need to get oxygen from the environment to stay alive.
Even though roots are buried, they can absorb oxygen from the small air spaces in soil. This is why it\’s possible to \’drown\’ plants by watering them too much. If the soil is way too wet, the roots are smothered, the roots can\’t get any oxygen from the air, and the cells in the roots die. Without those root cells, the rest of the plant dies. Some plants have evolved adaptations to deal with extremely wet soil. Mangroves are trees that live in swampy environments along the coast in the tropics. The roots of mangroves are often entirely under saltwater, so they have special structures called pneumatophores (Greek for \”air carrier\”) that act like snorkels, sticking up out of the water to get a oxygen for the roots. Click to return to the search form. By Ilana Goldowitz Jimenez, You probably know that plants generate oxygen during photosynthesis. Since itБs common knowledge that plants take in carbon dioxide and release oxygen into the atmosphere during this process, it may be a surprise that plants also need oxygen to survive. , plants take in CO2 (carbon dioxide) from the air and combine it with water absorbed through their roots.
They use energy from sunlight to turn these ingredients into carbohydrates (sugars) and oxygen, and they release extra oxygen to the air. For this reason, the forests of the planet are important sources of the oxygen in the atmosphere, and they help keep the level of CO2 in the atmosphere low. Is Oxygen Necessary for Plants? Yes, it is. Plants need oxygen to survive, and plant cells are constantly using oxygen. Under certain circumstances, plant cells need to take in more oxygen from the air than they generate themselves. So, if plants generate oxygen through photosynthesis, why do plants need oxygen? The reason is that plants respire, too, just like animals. Respiration doesnБt just mean Бbreathing. Б It is a process that all living things use to release energy for use in their cells. Respiration in plants is like photosynthesis run backwards: instead of capturing energy by manufacturing sugars and releasing oxygen, cells release energy for their own use by breaking down sugars and using up oxygen. Animals take in carbohydrates for respiration through the food they eat, and their cells constantly release the energy stored in food through respiration.
Plants, on the other hand, make their own carbohydrates when they photosynthesize, and their cells use up those same carbohydrates through respiration. Oxygen, for plants, is essential because it makes the process of respiration more efficient (known as aerobic respiration). Plant cells are respiring constantly. When leaves are illuminated, plants generate their own oxygen. But, during times when they canБt access light, most plants respire more than they photosynthesize, so they take in more oxygen than they produce. Roots, seeds, and other parts of plants that donБt photosynthesize also need to consume oxygen. This is part of the reason plant roots can БdrownБ in waterlogged soil. A growing plant still releases more oxygen than it consumes, overall. So plants, and the plant life of the earth, are major sources of the oxygen that we need to breathe. Can plants live without oxygen? No. Can they live on just the oxygen that they produce during photosynthesis? Only in the times and places where they are photosynthesizing faster than they are respiring.