This document provides a cheat sheet on key plant function concepts for AP Biology including plant hormones, reproduction, and defense. It lists the five major plant hormones- auxins, cytokinins, gibberellins, abscisic acid, and ethylene- and their effects on processes like cell growth and dormancy. Plant reproduction structures like flowers and their male and female parts are defined. Finally, it outlines natural physical and chemical barriers to pathogens as well as inducible defense responses like systemic acquired resistance.