‘ We are Clownífics! ‘is a fun science series for girls and boys made by Big Van Ciencia, a team that carries out scientific dissemination activities for all types of audiences. Here Orilo and Arlequino will explain hilarious scientific stories and very scientific home experiments, with lots of humor and fun.
In this chapter, Harlequino asks Orilo this question: why do the leaves fall from the trees when autumn comes? To understand it, it is essential to know a little more about how trees work. In order to carry out daily activities, all of us need energy, and we get that energy from food.
Plants do not have a mouth, and their way of feeding is a little different from that of animals. It could be said that trees “eat for the leaves” through a process called photosynthesis, which is the mechanism that plants use to capture carbon dioxide from the atmosphere, water from the ground, gather everything together, and thanks to the sun’s energy obtain their own sugars. And this is how the trees feed.
Thanks to photosynthesis, which is done in the leaves, the trees feed, but what happens when winter arrives? The leaves of the trees could freeze, and there is also much less sunlight, which means that the trees can no longer photosynthesize and that is why some of these trees, the so-called deciduous, prefer to lose their leaves.
What happens in the trees during the winter?
Harlequin has a new doubt: if the trees lose their leaves, then they are stopping eating. How then do they manage during that period? We could not stop eating between autumn and spring … what trees do is hibernate: during winter they accumulate all the energy they can within their trunks, and in addition there is a decrease in almost all activity. To accumulate energy, in autumn, before losing the leaves, the trees suck all the nutrients that had accumulated in them, including chlorophyll, responsible for the green color, and that is why they also turn brown. These nutrient-free leaves eventually shed from the branches.
When spring comes, the leaves grow back on the trees, and then all the usual activity begins anew. At that time there is much more light for photosynthesis to work at full capacity. How clever are the trees!
