15. DEOXYGENATED BLOOD IS BLOOD RICH IN OXYGEN 16. DURING RESPIRATION, A PERSON INHALE AND EXHALE 17. ARTERIES ARE THICK- WALLED AND ELASTIC 18. THE BLOOD IS MADE UP OF PURELY LIQUID MATERIALS 19. THERE ARE ABOUT SIX LITERS OF BLOOD IN THE HUMAN BODY 2O. THE HEART AND LUNGS WORK WELL DURING COMPLETE CIRCULATION