Red blood cells make up about 40% of our blood.
WE’VE all seen blood before. Whether it was our own or on TV, we recognise it immediately because of its red, gooey appearance. But what exactly is blood, and what does it do? And, is everyone’s blood the same?
WHAT IS BLOOD?
Blood is a red fluid that constantly circulates in the body through veins, arteries and capillaries (blood vessels). Each time your heart beats, it pumps oxygen-carrying blood to every part of your body via arteries. Once this oxygen has been delivered, the deoxygenated blood travels back to the heart via your veins, where it is sent back to the lungs to collect