I think it's light dependent and the light independent take place outside the thylakoid membranes.
It's a way of protecting the trees, and making sure they survive the winter and beyond. Leaves die during the winter months. If those dead leaves stayed on the trees, and new ones wouldn't grow in their place, the tree would have no way of making food for themselves.
Hope it helps. ☺
Answer:
Eat fig and do exercise every day
