Britannica: "During photosynthesis in green plants, light energy is captured and used to convert water, carbon dioxide, and minerals into oxygen and energy-rich

Britannica: "During photosynthesis in green plants, light energy is captured and used to convert water, carbon dioxide, and minerals into oxygen and energy-rich organic compounds". Getting the Carbon from CO2 gets the backbone of organic compounds. Getting the Hydrogen from H2O is also necessary and is also part of photosynthesis. We have chemosynthetic bacteria on earth that use chemical energy rather than light. There is also a hypothetical biological process called radiosynthesis: https://en.m.wikipedia.org/wiki/Radiotrophic_fungus https://en.m.wikipedia.org/wiki/Radiotrophic_fungus I am not a biologist - but I find biology fascinating!