Photosynthesis and cellular respiration are complementary processes that are crucial for the survival of all living organisms. Photosynthesis converts light energy into chemical energy, which is then used to synthesize organic molecules such as glucose, the primary source of energy for most living things. The oxygen produced by photosynthesis is also essential for most forms of life, including humans.

Cellular respiration, on the other hand, breaks down organic molecules to produce energy in the form of ATP, which is used to power the various metabolic processes of the cell. Although most organisms use glucose as their primary energy source, other organic molecules such as fats and proteins can also be catabolized to produce ATP.

Overall, photosynthesis and cellular respiration are intimately linked, with the products of one process serving as the raw materials for the other. Together, these two processes form an intricate web of energy flow that sustains life on this planet.