What you’ll learn4 learning objectivesChoose one objective for a focused lesson, or study the complete topic.14.2.1Stomata response to environmental changes• Stomata response to environmental changes: balance CO2 uptake by diffusion with minimising water lossSyllabus objective14.2.2Daily rhythms of stomatal opening and closing• Daily rhythms of stomatal opening and closingSyllabus objective14.2.3Guard cells• Guard cell structure and function in stomatal mechanismSyllabus objective14.2.4Abscisic acid and stomata• Abscisic acid role in stomatal closure during water stress: calcium ions as second messengerSyllabus objective