Final answer:
The main reactants in photosynthesis are carbon dioxide and water, and the primary product is sugar, or glucose. This process, where plants convert light energy into chemical energy, also produces oxygen as a byproduct.
Step-by-step explanation:
The main reactants in photosynthesis are carbon dioxide and water; the main product is sugar, specifically glucose. Photosynthesis is a vital biological process wherein plants utilize energy from sunlight to convert carbon dioxide and water into glucose, which serves as an energy source for living organisms, and oxygen, which is essential for respiration in animals and humans. This transformation of light energy into chemical energy occurs within the chloroplasts of plant cells.
In a simplified chemical equation, photosynthesis can be represented as 6CO2 + 6H2O + Energy → C6H12O6 + 6O2. Here, the reactants on the left, along with sunlight as energy, produce the glucose and oxygen on the right. Oxygen, while being essential for life on Earth, is considered a byproduct of this process.