At a glance Figures View all figures Figure 1: Arrows in scientific diagrams. (a) Well-understood conventions in molecular biology indicated by arrows. (b) Arrows are defined loosely by their geometric shapes and more definitely in context. (c) A diagram with 19 arrows used as leaders, to indicate reagent flow and to show mechanical movement. Reprinted from Nature Methods3. Full size image View in article Figure 2: Functional qualities of arrows. (a) The use of arrows versus lines as connectors suggests a certain functional relationship. (b) Alternatives to arrows as leader lines. (c) Reasonably sized arrows clearly indicate direction without being a distraction. (d) Trapped whitespace in 'open' arrowheads creates optical illusions that can attract unwanted attention. (e) Whitespace at the ends of the arrows makes them easy to discriminate from other content. (f) Orienting arrows in similar directions creates natural visual flow. Full size image View in article