Why do Plants photosynthesis and RESPIRE? I thought respiration was a human thing?
All living things in this world must go through a process called cellular respiration, without it, it would be impossible for life to exist. Cellular Respiration makes use of the energy within an electron to produce the universal biological energy molecule, ATP. The respiration you are referring to is what allows for the absorbtion of oxygen and release of carbon dioxide from an animal. Animals still go through cellular respiration as well, but it is much more important to understand the cycle in plants.
When plants absorb light energy through photosynthesis, they are enacting their own form of cellular respiration in order to form organic molecules such as sugars. What is unique about photosynthesis is that is precisely the opposite chemical reaction displayed in cellular respiration. Organisms such as bactera (and even humans) must break down outside organic elements, which in turn releases electrons. These electrons can then be converted into the ATP energy molecule. Plants, on the other hand, use sun energy to convert carbon dioxide directly into ATP. The plant will then break down the ATP molecule into electrons so that it can obtain organic compounds necessary for survival, such as sugar.
You can probably now see that without photosynthesis us non-plant organisms would have some trouble finding organic compounds to break down. So the next time you eat something, thank photosynthesis.
