During photosynthesis, plants convert simple carbon dioxide into energy-rich compounds. They absorb carbon dioxide from the air. Sunlight provides the energy for this. The Greek word “photo” means light, the word “synthesis” means “composition”. So something is put together with the help of light.
Photosynthesis occurs in the green parts of plants. They are green because they have small pieces of green pigment in their cells. This pigment is called chlorophyll. It first breaks down the carbon dioxide and then reassembles it into glucose with the help of sunlight. In German, glucose is simply called grape sugar. For this process, the plant needs additional water, which it absorbs with its roots.
Another substance is produced during photosynthesis, namely oxygen. But the plants don’t need it. That’s why they put it back in the air.
Photosynthesis is so important for us humans because when we breathe, we and all animals do exactly the opposite of what plants do: we need the oxygen that we breathe in through the air. When we breathe out, carbon dioxide is released back into the air. This is a cycle in nature that never ends.
However, humans and animals also use the sugar produced by photosynthesis. Vegetables, fruit, grains, and many other foods are made from them. But wood, cotton, and many other things are only created with the help of photosynthesis.