They come from the atmosphere, since plants use carbon dioxide to produce carbohydrates :)
Answer:
In plants photosynthesis occurs in two steps light-dependent stage and light-independent stage.
ATP is energy carrier and NADPH is electron carrier and both are produced during the first step from the sunlight as they carry the energy and electron to the next step which is light-independent step. In this step both ATP and NADPH are used in the formation of sugars from carbohydrates.
Therefore, these molecules connect the light-dependent and light- independent reactions of photosynthesis.
Because warm air rises up so it's warmer on the top floor.
