Final answer:
Photosynthesis in plants requires three essential components: sunlight, carbon dioxide, and water. These reactants are processed within the plant's chloroplasts to produce glucose and oxygen.
Step-by-step explanation:
The process of photosynthesis requires three key components: sunlight, carbon dioxide, and water. These three items are crucial reactants that plants use to produce energy. Carbon dioxide and water enter the plant cells and meet in the chloroplasts. There, with the help of sunlight, they undergo a series of complex reactions to produce glucose, a sugar molecule, and oxygen, which is released as a byproduct. This process is essential for converting the energy from sunlight into a usable form of energy for the plant, and it also produces the oxygen we breathe.