What is the difference between oxygenated and deoxygenated blood?

Oxygenated blood contains oxygen, while deoxygenated blood does not.

Oxygenated blood is blood that has been oxygenated in the lungs. This occurs when the blood passes through the pulmonary capillaries, where it picks up oxygen from the air we breathe. The oxygen then binds to haemoglobin in the red blood cells, forming oxyhaemoglobin. Oxygenated blood is bright red in colour and is pumped from the heart to the rest of the body via the arteries.

Deoxygenated blood is blood that has already delivered its oxygen to the body's tissues and is returning to the heart to be re-oxygenated. It is dark red in colour and is pumped from the body to the heart via the veins. Deoxygenated blood is then pumped to the lungs, where it is oxygenated and the process starts again.

The difference between oxygenated and deoxygenated blood is important for understanding how the circulatory system works. Oxygenated blood carries oxygen and nutrients to the body's tissues, while deoxygenated blood carries waste products such as carbon dioxide away from the tissues. The heart plays a crucial role in this process, pumping oxygenated blood to the body and deoxygenated blood to the lungs.