The underside of the leaves absorb light


Plants breathe too - but with what?

No being can live without air, humans, animals and plants. But plants don't have a nose or a mouth - how are they supposed to breathe?

Plants that grow on land have tiny stomata called stomata on the underside of their leaves. Stomata comes from the Greek word "stoma" which means mouth. They breathe with these little mouths.

The great thing about plants is that they breathe in carbon dioxide, which in excessive amounts is harmful to us and our environment. And what's even better is that they also produce oxygen in the process.
It's a rather complicated process called photosynthesis.

No photosynthesis without light

Plants have a unique substance - chlorophyll. And that not only makes the leaves green, but also turns water and carbon dioxide into sugar and oxygen with the help of light. The plant stores the sugar, but releases the oxygen again.

Plants do that quite effectively. A hundred-year-old beech releases about as much oxygen into its surroundings via its leaves in one hour as 50 people need to breathe!

Rainforest supplies the world with air

The rainforest supplies the most oxygen. Tropical rainforests are mainly found in South America and Asia. So many trees and plants grow here that they can supply the whole world with oxygen - even if all trees in Europe had no leaves in winter.

Do plants also need oxygen?

Yes, in cellular respiration. The plant needs this process in order to obtain energy from the stored sugar.

For this, the sugar has to be crushed and the plant does this with the help of oxygen. With the energy released in this way, the plant allows its shoots to grow or to drive out its roots.

Overall, however, plants produce significantly more oxygen than they consume. It is actually thanks to them that people have enough oxygen to breathe - and should therefore be particularly careful with the plants.