Veins are blood vessels that carry deoxygenated blood back to the heart. While veins carry blood that has less oxygen, they still contain some oxygen.
The major difference between arteries and veins is the type of blood they carry. Arteries carry oxygenated blood from the heart to the body, while veins carry deoxygenated blood back to the heart to be re-oxygenated by the lungs.
It's important to remember that even though veins carry deoxygenated blood, this blood still contains some oxygen. This is because the blood has not yet been completely depleted of oxygen as it travels through the body.
The oxygen content of the blood in veins is lower than in arteries, but it is not completely devoid of oxygen.
