What you’ll learn3 learning objectivesChoose one objective for a focused lesson, or study the complete topic.15.2.1Venus fly trap rapid response• Venus fly trap rapid response: stimulation of hairs, trap closure mechanismSyllabus objective15.2.2Auxin role in elongation growth• Auxin role in elongation growth: stimulates proton pumping to acidify cell wallsSyllabus objective15.2.3Gibberellin role in barley germination• Gibberellin role in barley germinationSyllabus objective