Red and blue are teaching colours: oxygen-poor blood is dark red, not blue. Speeds and the heartbeat are a teaching approximation.
Not to scale: an air sac is about a quarter of a millimetre across; a bronchiole about one millimetre.
3D models: VOKA 3D Anatomy, as used in G8 Anatomy.
How it works: based on Human Blood System by Christian Pasín Rey, github.com/christianpasinrey/human-blood-system. MIT licence, © Christian Pasín Rey. The blood cell flow, ECG trace, heart sounds, organ cards and views are ported from it; the organ text is adapted from it.
Changes for G8 Circulation: the cells follow the centre lines of the VOKA vessels in closed loops through the body and the lungs, with a pulse in the arteries; the VOKA heart beats and the lungs breathe (G8 Anatomy's motions); Gener8's wall layout, touch controls and saved views.
MIT licence: Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND.
Heart attack and stroke: Gener8. Coronary and cerebral routes along VOKA's own arteries; the starved tissue, the ECG changes and the artery close-up (plaque, clot, stent) are teaching approximations based on NICE NG185, NG126 and NG128.
DVT and embolism, aneurysms: Gener8. The clot's journey, the swollen calf, the ballooning aorta and stent graft, the berry aneurysm and coils are teaching approximations based on NICE NG158, NG156 and NG228.
Asthma and COPD: Gener8. Levels, breathing, oxygen saturation and spirometry are teaching approximations based on the BTS/NICE/SIGN asthma guideline (2024), BTS acute asthma severity bands and the GOLD 2026 COPD report.
Educational model. Speeds, timings and colours are a teaching approximation, not for diagnosis or treatment.