Gardener's Dictionary: Phototropism
Phototropism (n): The movement of a part of a plant toward or away from a light source. Sunflowers are heliotropes, and their flower heads follow the sun throughout the day.
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Phototropism (n): The movement of a part of a plant toward or away from a light source. Sunflowers are heliotropes, and their flower heads follow the sun throughout the day.