photosynthesis: Quick Facts

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Last updated

Nov. 13, 2026

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Photos and Videos

Diagram of a tree leaf illustrating photosynthesis, with arrows showing sunlight, water, and carbon dioxide entering the leaf and sugars and oxygen being produced. A person is shown beside the tree to demonstrate the exchange of oxygen and carbon dioxide between plants and animals.

Colored scanning electron micrograph showing green, bead-like cyanobacteria filaments intertwined, with several round, spiky pink spores scattered among them.

A diagram shows the process of photosynthesis, where carbon dioxide and water, using light energy and chlorophyll in leaves, are converted into glucose and oxygen. The chemical equation 6CO2 plus 6H2O yields C6H12O6 plus 6O2 is displayed.

Diagram of a chloroplast showing its structure, including the outer and inner membranes, stroma, thylakoids stacked into grana, stroma lamellae, lumen, and intermembrane space.

Diagram of the light reactions of photosynthesis

Diagram illustrating noncyclic electron flow in photosynthesis, showing the movement of electrons from photosystem II to photosystem I through various molecules and complexes, with light energy driving the process.

Diagram showing chemiosmosis in chloroplasts during photosynthesis, with protons moving across the thylakoid membrane through ATP synthase to produce ATP from ADP and phosphate, and a labeled chloroplast structure.

Diagram of the reductive pentose phosphate cycle in photosynthesis, showing carbon dioxide fixation and reduction steps. Arrows trace the transformation of CO2 and RuBP through intermediates like PGA, DPGA, and Gal3P, with ATP and NADPH inputs and the net production of one Gal3P molecule for sugar or starch synthesis.

Rows of tall green corn plants with yellow tassels stretch into the distance in a Nebraska agricultural field.

Learn About the Greenness of Plants

Learn How the Layered Arrangement of Chlorophyll Molecules Within a Leaf Increases Its Photosynthetic Output

How Does Photosynthesis Work?

The Relationship Between Photosynthesis and Breathing

The Process of Photosynthesis in Plants Explained

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Topics

Hill reaction cyclic electron flow pheophytin carbon fixation photosystem II photosystem I photorespiration Crassulacean Acid Metabolism photophosphorylation noncyclic electron flow death plant development coloration Sex sleep plant reproductive system Biological development aging Excretion mimicry

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Key People

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Robert Hill

British biochemist

Joseph Priestley

Joseph Priestley

English clergyman and scientist

Melvin Calvin

Melvin Calvin

American biochemist

Ingenhousz, detail of an engraving

Jan Ingenhousz

Dutch-born British physician and scientist

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Jean Senebier

Swiss botanist

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Robert Huber

German biochemist

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Johann Deisenhofer

German American biochemist

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Nicolas-Théodore de Saussure

Swiss scientist

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Hartmut Michel

German biochemist

greylag. Flock of Greylag geese during their winter migration at Bosque del Apache National Refugee, New Mexico. greylag goose (Anser anser)

Biology Bonanza

Photosynthesis diagram showing how water, light, and carbon dioxide are absorbed by a plant and that oxygen and sugars are produced. Also show a person to illustrate the oxygen/carbon dioxide cycle between plants and animals.

Pop Quiz: 13 Things to Know About Photosynthesis