Plants could live if all the oxygen were removed IF they had the light, water, and carbon dioxide needed to do photosynthesis. BUT they probably could not survive if the oxygen were not allowed to build up again. As you may know, when plants do photosynthesis, they use the energy in light to put the matter in water and carbon dioxide together into carbohydrates like sugar. Oxygen is a byproduct of photosynthesis.
Here’s the part that most people don’t get. Plants have to do cellular respiration too, just like us animals. Photosynthesis happens only in specific cells, like some of the cells within the leaves of trees.
As I look out my window, I see trees with no leaves. Those trees are not dead, so where are they getting the energy to stay alive? They’re breaking down the sugars they made when their leaves were doing photosynthesis. In cellular respiration, oxygen is needed to allow the sugar to be broken back down into carbon dioxide and water, which will release the energy needed by all cells to stay alive.
Look out your window at a tree or imagine one. How much of that tree can do photosynthesis, even when the tree has leaves? Only a small fraction of the total number of cells can. Many of the cells are never even exposed to light. Even the cells that can do photosynthesis don’t have light all the time. When it’s night, or cloudy, or that particular leaf is in the shade, it’s all cellular respiration.
The first stage of cellular respiration (glycolysis) doesn’t require oxygen, but it only releases about 2 energy units compared to about 36 energy units from doing all the stages. If you imagine getting only about 1/18 of your normal food intake, you can see how this would be a problem for a plant.
How do oxygen and carbon dioxide get in and out of the plant’s leaves and cells?
Thanks for asking,