The natural resource essential for the process of photosynthesis is sunlight, specifically the visible light portion of the electromagnetic spectrum. During photosynthesis, plants, algae, and some bacteria capture sunlight using chlorophyll, the green pigment found in their cells. This light energy is then used to convert carbon dioxide and water into glucose and oxygen. Glucose serves as an energy source for the plant, while oxygen is released into the atmosphere as a byproduct. This process is fundamental for sustaining life on Earth, as photosynthesis not only provides food for plants but also produces the oxygen necessary for most living organisms.