Photosynthesis is a process where plants use sunlight, carbon dioxide, and water to produce sugars and oxygen. It's crucial for life on Earth because it provides food for plants, which are the base of the food chain. Additionally, photosynthesis produces oxygen, necessary for most living creatures to breathe.
Imagine you are an alien botanist studying Earth's plant life. Briefly describe the process of photosynthesis and its importance to life on Earth.