2. The production of organic substances, primarily sugars, from carbon dioxide and water which occur in green plant cells.
3. The fundamental chemical process in which green plants (and certain other organisms) utilize the energy of sunlight or other light to convert carbon dioxide and water into organic chemical energy.
Photosynthesis is often described as the most important chemical reaction on earth and is found in bacteria, cyanobactria, algae, and most plants.
The coupling of light energy to chemical energy is, directly or indirectly, the basis for nearly all life on earth.
"From sea slugs to salamanders, many animals can naturally tap into solar power"
There are plenty of free-living photosynthetic animals; including photosynthetic flatworms up to 15 millimetres long that can be found in huge numbers in places.
Then there are the jellyfish-like Vellela, which float on the sea surface, and the upside-down jellyfish. Most striking of all are the many different kinds of solar-powered sea slugs.