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How do plants use carbon dioxide and water to make carbohydrates?

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Underwater view of a glowing chain of tunicates with a scuba diver and boat visible near the water's surface in the background. — photochemical reaction Chain of fluorescent tunicates.

Plants produce carbohydrates through photosynthesis, a two-stage process that converts light energy into chemical energy to synthesize organic compounds from carbon dioxide and water.12

The Two Stages of Photosynthesis

Light Reactions: Occurring in the chloroplast grana, these photochemical reactions capture light energy using pigments like chlorophyll. This energy drives the oxidation of water, releasing oxygen and generating ATP and NADPH.12
Dark Reactions: Taking place in the stroma, these enzyme-controlled reactions do not require light directly. Using the ATP and NADPH produced in the light stage, plants perform carbon fixation via the Calvin-Benson cycle. During this cycle, carbon dioxide is attached to a five-carbon compound and eventually converted into glucose and other carbohydrates.132

The overall chemical process is summarized by the equation:
$6 C O_{2} + 12 H_{2} O \to C_{6} H_{12} O_{6} + 6 O_{2} + 6 H_{2} O$ 2