What is the main function of starch in plants?

When a plant takes in carbon dioxide from the atmosphere and receives adequate sunlight and water, chloroplasts in the plant's cells convert the reactants, water and carbon dioxide, into oxygen and glucose. Glucose is stored in the tissue of the plant for food and energy. In essence, this is the process of photosynthesis. Glucose is often stored in plants in the form of starch, which is composed of glucose molecules linked in long chains.

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Plants, sunlight, growth and artificial sunlight

Iwould say silver and gold