All veins carry deoxygenated blood

Arteries & veins

With each heartbeat, the heart pumps blood in the vessels around the body. Blood vessels that lead from the heart into the body are called Arteries'Back to the heart it's over Veins. The human vascular network is reminiscent of a tree: the trunk of the tree is the main artery (aorta). Thick main branches branch off from the aorta and branch out into smaller blood vessels (arterioles). At the very end of the "branches" are the smallest vessels, which are called hair vessels or Capillaries are designated. In this capillary network, the oxygen is released into the cells and tissue. Then the capillaries collect again to form larger vessels and are now called Venules. The venules open into even larger veins, which later carry the blood through the upper or lower vena cava (Vena cava) lead back to the heart.

Almost all arteries contain oxygen-rich blood; most veins contain oxygen-depleted blood. Oxygenated blood is light or bright red compared to dark red oxygen-poor blood. When blood is drawn, the doctor takes blood from a vein, which is why the blood usually looks dark red. In many drawings, the oxygen-rich arteries are shown in red and the oxygen-poor veins in blue - but be careful: in the arteries that lead from the right heart to the lungs, oxygen-poor, dark red blood flows, while the blood in the veins from the lungs to the left heart is oxygenated and therefore oxygen is bright red.