Answer:
1. The Sun is the major source of energy for organisms and the ecosystems of which they are a part. Producers such as plants, algae, and cyanobacteria use the energy from sunlight to make organic matter from carbon dioxide and water
2.red coloration comes from a pigment called anthocyanin, which has to be made afresh as autumn takes hold.
3.Respiration: C6H12O6 + 6O2 → 6CO2 + 6H2O.