How does chemical coordination occur in plants?

Plants don't have a nervous system. Instead, they use chemical messengers called hormones. These are made in one part of the plant and travel to other parts to control things like growing toward light, ripening fruit, or dropping leaves.

Plants lack a nervous system and use chemical coordination through plant hormones (phytohormones). These are organic compounds produced in specific regions and transported to target sites: 1. Auxins — Synthesised at shoot and root tips. Promote cell elongation, apical dominance, and tropic responses. 2. Gibberellins — Promote stem elongation, seed germination, and fruit growth. They break seed dormancy. 3. Cytokinins — Promote cell division and delay leaf ageing. They are present in regions of active growth like root tips and developing fruits. 4. Abscisic acid (ABA) — Acts as a growth inhibitor. Promotes leaf fall (abscission), seed dormancy, and closes stomata during water stress. Unlike animal hormones, plant hormones can diffuse freely or travel through xylem and phloem. Their effects depend on concentration and the target tissue's sensitivity.