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How do chloroplasts use sunlight to make carbohydrates in plant cells?

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Artist's illustration of human nerve cells showing a central neuron with a green nucleus, branching dendrites, and glowing signals traveling along axons against a dark background. — cell Artist's conception of a human neuron.

Chloroplasts facilitate photosynthesis through two interdependent stages that convert light energy into carbohydrates.1

The Light Reactions

Occurring in the grana, these reactions capture light using pigment molecules like chlorophyll. When light is absorbed, it initiates an electron flow that generates chemical energy in the form of ATP and NADPH. Additionally, water molecules are dissociated into protons and oxygen gas during this process.1

The Dark Reactions

Taking place in the stroma, these carbon-assimilating reactions use the ATP and NADPH produced in the light reactions to convert carbon dioxide into simple sugars. Through the Calvin-Benson cycle, carbon dioxide is combined with ribulose 1,5-bisphosphate to eventually produce glucose.1

The overall chemical process is represented by the formula:
$6 C O_{2} + 12 H_{2} O \to C_{6} H_{12} O_{6} + 6 O_{2} + 6 H_{2} O$ 1