What is photosynthesis?

Photosynthesis is the process by which plants, algae, and some bacteria convert light energy into chemical energy in the form of glucose. During this process, these organisms take in carbon dioxide from the air and water from the soil, using sunlight as the energy source to combine them. The reaction primarily occurs in the chloroplasts of plant cells, where chlorophyll absorbs light, typically from the sun. This leads to the production of glucose, which serves as a vital energy source for the plant, and oxygen, which is released as a byproduct into the atmosphere.

The other options do not accurately capture the essence of photosynthesis. The respiration process in animals involves converting nutrients into energy but does not utilize light. Cellular division relates to how cells replicate and divide, which is separate from the energy-making process of photosynthesis. Lastly, while chemical reactions occur in the atmosphere, they do not define photosynthesis, which is a specific biological process within plants and photosynthetic organisms. Thus, the definition of photosynthesis as the process of using light to create energy aligns perfectly with its role in the ecosystem.