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Summary
DescriptionPhototropism Diagram.svg
English: 1. This is a normal plant that has the sun positioned almost directly over the plant. During this time, the auxin (pink dots) that lies within the plant is evenly distributed. 2. The sun is now positioned at an angle to the plant. The repositioning of the sun causes the auxin to move the other side of the plant, and becomes more concentrated. This overload of auxin next to these cells causes them to start to grow or elongate. 3. This results in the the plant to look like it is growing toward the sun. 4. If the sun moves to the other side of the plant, the auxin would again move to the other side of the plant and become concentrated on the side of the plant that is farthest away from the sun. 5. The same growth or elongation of the cells on this side of plant would continue to grow towards the sun.
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