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.
Oxygen (O2) is the only by-product of photosynthesis. 6 molecules of Carbon-dioxide and 6 molecules of water make 1 molecule of glucose as the main product, and 6 molecules of Oxygen as the by-product.