1. Full of or characterized by animation, vigor, or courage: a spirited debate. 2. Having a specified mood or nature. Used in combination: high-spirited; low-spirited.
One product of photosynthesis is glucose (sugar), which provides the basis for most food chains. The second product of photosynthesis is oxygen which comes in handy if your happen to be an aerobic organism that requires oxygen for survival.
Photosynthesis: Chemical process by which plants containing chlorophyll use sunlight to manufacture their own food by converting carbon dioxide and water to carbohydrates, releasing oxygen as a by-product. Respiration: The process in which oxygen is used to break down organic compounds into carbon dioxide and water.