Zoom from the whole body (meters) to organs (centimeters), cells (micrometers) and molecules (nanometers). The time ruler zooms from years down to nanoseconds; each level has its own natural timescale. Simulations show mechanisms and relative changes, not clinical values. Anatomy: BodyParts3D, © The Database Center for Life Science, licensed under CC Attribution 4.0 International. Protein shapes: RCSB PDB and the AlphaFold Protein Structure Database (CC BY 4.0). Molecules: PubChem.