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Below are a few major topics for this chapter, listed in random order.

• Apical dominance. Hint
• Auxin and acid growth. Hint
• Gibberellin. Hint
• Gravitropism. Hint
• Leaf abscission. Hint
• Phototropism. Hint
• Phytochrome signal transduction. Hint
• Thigmotropism. Hint
• Signal transduction. Hint

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Note: this is not a complete list of test topics.