understanding the blood circulation system heart, arteries, veins, and capillaries

atrium vena education red hepatic oxygen editable cava cross vien renal blue healthcare venous kidney organism background white graphic internal circulatory drawing lungs vein bloodstream pulmonary artery cardiovascular cardiology anatomical aorta medicine organ medical anatomy body vector human flow biology health blood heart diagram system circulation science understanding arteries veins capillaries transports nutrients waste ensuring vital functions font line cartoon brand text circle nose presentation hand face eye head arm logo advertising