TABLE OF CONTENTS Nature set herself the task of capturing the light flooding toward the earth and of storing this, the most elusive of all forces, by converting it into an immobile force the plant world constitutes a reservoir in which the fleeting sun rays are fixed and ingeniously stored for future use, a providential measure to which the very existence of the human race is inescapably bound.
Julius Robert Mayer, The Organic Motion in its Relation to Metabolism, 1845.
The word photosynthesis means building up by light , and the process is the building up, by plants, algae and certain bacteria under the action of sunlight, of organic compounds (mainly carbohydrates) from two very simple inorganic molecules, water (H 2O) and carbon dioxide (CO 2). Put another way, photosynthesis is the light-driven reduction of atmospheric carbon dioxide by water to energy-rich organic compounds. But this reductionist, chemist's view gives little hint of the central role of photosynthesis in sustaining life on Earth. Photosynthesis is the primary engine of the biosphere, essential to life since it is almost the sole process by which the chemical energy to maintain living organisms is made. It provides all our food, either directly in the form of green plants or indirectly in the form of animals that...
