How are photosynthesis and cellular respiration important to living things?

Cellular respiration, on the other hand, is the process by which living thingsconvert oxygen and glucose to carbon dioxide and water, thereby yielding energy. ... While photosynthesisrequires energy and produces food,cellular respiration breaks down food and releases energy.

By water evaporation from the leaves is created a negative pressure at the top of the tree that promotes the ascension  of the water through channels that are called xylem. there are also two molecule forces that are involved: the intra-water molecules cohesion (water molecules stick to each other) and the adhesion when the water molecules stick to the channels they are running in. this is what enables water to go from the roots to the top of a tall tree.